Master's Thesis
by AuronLu
Summary: Returning home with the cure to a deadly plague, Nyssa finds the Master meddling with her own past, the Doctor's future. Faced with time paradoxes, she turns to Tegan for help. Meanwhile, the Doctor races to keep time from unraveling. If they fail, the cost may be the lives of Nyssa's family, her adopted planet, or all the Doctor's future regenerations. [Big Finish, older!Nyssa]
1. Time Slip

The gentle hum of the TARDIS gave nothing away, nor did the faint clucks and beeps issuing from the console room. Nevertheless, the Doctor did not hurry his stride towards the flight deck, where someone was covertly setting his ship in motion. There were only three people he trusted with her inner workings. One he had left behind in e-space, another was safe in 22nd century London, and the last was a student pilot at best. Even so, Nyssa's competence was a secret source of pride for him. Once he had fostered her for the sake of her murdered father, until she outgrew the nest. It was a rare treat to have a former fledgeling circle back on graceful, steady wings, flying alongside him once more.

For a while.

"So," he said, thrusting his hands into his pockets. He was not surprised to see that Nyssa had changed back into the survival suit she had been wearing when they discovered her scouting on Helheim. "I take it that our pleasant reunion is coming to an end?"

She flinched, jabbed a button to clear the navigation screen, and turned to face his affable smile. "I'm sorry, Doctor. It's difficult to enjoy the scenic route, however dear the company, knowing there's an epidemic waiting for me back home." She nodded towards a black canister sitting next to the hatstand. "I've synthesised enough antiviral to get started, but it's helping no-one here."

"I understand. It's selfish of us to be keeping you from your work. Oh, good morning, Turlough, Tegan. Come to see Nyssa off?"

The pair had straggled in behind him, Turlough finishing a coffee that shouldn't have been on the flight deck, Tegan visibly drooping at the Doctor's words. The lean young man was still dressed in his black school uniform for reasons best known to himself, despite his avowed loathing for Earth, the British school system, and anything to do with the backwater planet where he had been exiled. Tegan, the only human among them, was sporting a loud parti-coloured top, leather skirt and high heels. Her outfit reminded the Doctor of one of those species who warned off trespassers with bold markings.

"Leaving so soon?" Turlough drawled, giving the Doctor a pointed glance. Time aboard the TARDIS was relative, of course, but it had been at least several weeks since they had offered Nyssa a lift home.

"Nyssa!" Tegan's mock-indignation sounded less joking than she probably intended. "You're not leaving me stuck with these two pillocks again, are you? I've half a mind to tag along and pass you your test tubes. But no, I'm forgetting, you've got someone else to—"

"Tegan." Nyssa embraced her, cutting her off. "I shall miss you."

Tegan clutched the smaller woman close, struggling to sound casual. "Well, it's not like it's forever goodbye, is it? I mean, you and I have both found our way back to the TARDIS once already."

"I don't know, Tegan."

"You're supposed to say something cheerful and encouraging, brainiac."

"Then I shall be sure to stock ice cream for your next visit."

"There you go!" Tegan said. "Did you hear that, Turlough? I think she just made a joke. In another fifty years, she'll have us in stitches."

"Wonderful," he said. "It will make a nice change from bandages and splints."

"Now, what's this?" said the Doctor, pulling up the settings that Nyssa had been entering when he arrived. "I may be growing forgetful, but it seems to me that these aren't the coordinates for Terminus. It occupies a rather unique position in space."

"Oh... no, not Terminus," Nyssa said, an odd catch in her voice. "You don't imagine I've been holed up there for fifty years, do you? We treated the last known case of Lazar's disease over a decade ago."

"You haven't told us much of anything about what you've been up to, really," Tegan said. "Apart from chasing intergalactic bugs with a flyswatter."

"Well, your eyes glazed over every time the Doctor and I started discussing my research. And I was on holiday, more or less." She glanced towards the medical container. "But it's past time for me to return to my laboratory."

"Does this laboratory have a name?" Turlough said. "A planet?"

"Very well." The Doctor stepped away from the console with a sweep of his hand. "Care to do the honours, Nyssa? One last time."

"Oh. Yes. Thank you, Doctor." She took his place and began to key in the materialisation sequence with subdued efficiency. The Doctor stared over her head, watching the time rotor as it began to rise and fall. His hand hovered over her shoulder for a moment, then dropped to his side.

Tegan turned away. She wanted to shout at both of them for _not_ shouting, _not_ arguing, for frittering away Nyssa's final moments aboard the TARDIS in banal routine. For once, Tegan kept her mouth shut, but she indulged in a petty wish for the ship to break down in transit. Just to spite her, it would probably arrive early for a change.

"Can't you teach me to do that?" Turlough said, watching Nyssa's hands dance across the controls.

"What, and give you a way to bolt whenever things get dicey?" Tegan said.

"He who fights and runs away lives to rescue his friends—"

"The next time will be the first."

"Children, children." The Doctor raised his hands. "The TARDIS is an immensely complicated and particular machine. Smooth operation requires mental rapport as well as practical knowledge. Nyssa is unusual in possessing the advanced technical skills, psychic sensitivity and _tact_ necessary to fly her."

"Tact?" Turlough snorted. "You're telling us the TARDIS needs coddling? Doctor, you punch the console about once a day to make it work."

Tegan laughed. "I guess that's why Nyssa's landings are smoother than—"

The floor bucked under them, throwing Tegan and Turlough against the wall. The Doctor lunged for the console to keep Nyssa from skidding under it.

"You were saying?" Turlough growled, wiping coffee from his eyes.

"Tachyon surge," Nyssa gasped. "Doctor, these readings—"

"I see it," he said, reaching around her. "Hold tight. Got to dodge the disruption. Materialise on my mark."

Even holding onto the console was difficult, let alone trying to operate it. The heaving of the floor grew more and more violent. Around the room, the roundels stuttered from light to dark and back again, their illumination dimming to a sickly amber. The lattice walls began to assume a milky, translucent sheen, through which a swirling maelstrom was becoming visible.

"That doesn't look good," said Tegan, edging away from the wall. "Is that the time vortex?"

"We're breaking up!" Turlough said. "Emergency landing, now!"

"Doctor?" Nyssa said, clinging to the lip of the console.

"Steady," said the Doctor, manoeuvering around her to operate buttons and levers in what Tegan recognized as mad improvisation. "Ready. Three... two... one... mark!"

He slapped both hands onto the controls as Nyssa threw the materialisation switch. There was a flash, a sizzling pop, acrid smoke rolling out of the central rotor like a steaming volcano, and an abrupt jolt. The TARDIS stopped moving so suddenly that everyone went flying. A faint hiss issued from the console, signalling that the fire suppression system had kicked in.

"You just had to leave us with a bang, didn't you?" Tegan said, offering Nyssa a hand up.

"So where are we?" Turlough said. "What did you say this planet was called?"

Tegan reached for the scanner toggle to look outside, but Nyssa caught her hand. "Wait. The controls are hot. Doctor, are you all right?"

"Fine, fine," he said, sprawled against the base of the doors. "Turlough, help me up, would you? Tachyon particles at that concentration make me rather giddy."

"So much for Nyssa's piloting skills," Turlough said, pulling the hatstand off of him.

She frowned but said nothing, covering her nose and mouth with her sleeve as she leaned down through wisps of smoke to examine the navigation screen. "The spatial coordinates are correct, but we've landed several decades too early."

"Nyssa's piloting skills aren't to blame. It was a powerful tachyon explosion penetrating the TARDIS' shielding," said the Doctor. "Nyssa, exactly what kind of research are they doing here?"

"Strictly medical, although some of the labs use radioactive materials. But there's nothing I can think of to explain these readings." She pointed. "Look. Cherenkov radiation."

"Is that dangerous?" said Tegan.

"We should leave at once," said Turlough.

"No," the Doctor said, stumbling over to take a look. "Minute levels, insufficient to harm living tissue. Surprisingly low, considering the scale of that disturbance. Fascinating."

"Doctor," Nyssa said. "Whatever caused it, there's no point in staying here. Can the TARDIS take off?"

"I'm afraid not," he said. "Auto-repairs will take some time. And that tachyon field poses a grave threat to any passing TARDIS. If we try to jump forward through it, it could burn out the stabilisers and leave us stranded in the time vortex. Or worse."

She frowned. "It should be simple enough to bypass the field of disruption, provided that we move laterally in space before the time jump."

"I'd rather not leave an obstacle like that on your doorstep, Nyssa. Come along. The origin of that explosion wasn't far from these temporal coordinates. Presumably, the source is outside." He reached for the door controls. "As your current self is on Terminus perfecting the cure for Lazar's disease, there's no risk of you bumping into yourself. Care to give us a tour?"

"Doctor, wait!" she said, but it was too late. He had already vanished outside with a flap of beige coattails. Shaking her head, she crossed the room to check the seals of her medical container. "I hope this wasn't damaged. I'll need to run a few tests."

"Aren't you coming?" Tegan said.

"Hang on. What's really going on here?" Turlough folded his arms. "Why is Nyssa being so secretive? What's so special about this place?"

"Nothing," Nyssa said. "But there's someone here I don't want to meet."

"An enemy?" Tegan said. "Not the person who set off that time bomb?"

Nyssa gave a weak laugh. "Hardly. He's a dream analyst."

They stepped out into a fragrant grove of conifers whose craggy red bark and feathery foliage captured the breeze in a rushing whisper like the sound of distant surf. Long needles carpeted the ground in a soft, springy weave studded with small white flowers pushing up through the thatch. Birdsong filtered through the treetops, while far-off voices and laughter carried on the wind. Stone buildings rose above the trees like canyon walls looming over a lake of green fog.

"Hey," Tegan said. "I thought you said we'd landed in the right spot. This isn't a medical lab; it's a city park!"

"They don't have to be mutually exclusive, you know. Patients heal better when they don't feel like prisoners." Nyssa spoke with some feeling. She had been one of the few patients to survive Terminus' brutally primitive facilities before she took over its administration.

"Now where has the Doctor got to?" Turlough said. "Typical. Asks you for a guided tour, then dashes off."

Nyssa sighed. "Let's go. There's an open quad in this direction."

"Stop fretting," Tegan said. "You're home! And it's gorgeous. I'm so glad, Nyssa. I know you must've spruced up Terminus after we left, but I always worried about you withering away on that dingy old space station."

"Yes," Nyssa said, tipping up her chin to breathe deeply. "Home. As peaceful a world as you'll find in this century. And some of your descendants settled here, Tegan. Look." She bent and plucked a small white bloom like a miniature daisy from a spreading ground cover.

Tegan took it from her and sniffed. "Mmm. Don't tell me... camomile?"

She nodded. "Most of the introduced plants are edible or medicinal. Oh, by the way, other genders are more visible here than on Earth or Traken. The TARDIS will translate, but you may hear a few unfamiliar pronouns."

Tegan's brow furrowed. "What, like Ziggy Stardust?"

"Perhaps." Nyssa caught Turlough's sardonic eyebrow and shrugged. "Come on."

They emerged at the edge of a roughly rectangular lawn encircled by a meandering path. Buildings bordered most of the quadrangle. Each had inset cavities, nooks and archways for the trees to spill into, blurring the interface between structure and nature. At the centre of the grassy area was a large fountain whose basin doubled as a sundial, occupied by several skinny dippers. Other students sat or sprawled on the stone rim or on benches surrounding the quad. Here and there, orderlies in pale blue uniforms escorted patients along the crushed-shell walkways.

Tegan noticed that most of the locals had dark olive or coppery-brown skin and wavy black hair. There were enough exceptions, however, that visitors stood out more by their clothes than their complexions. Casual campus attire ran to coveralls and clogs or tunics with leggings and low boots. Hoods, cloaks or pocket umbrellas poking out of knapsacks suggested unpredictable weather.

She grinned. "Hippie university. Why am I not surprised you ended up here?"

"No sign of the Doctor," said Turlough. "How does he do that?"

"Hullo," said a young man sitting on a nearby bench. He removed his earphones and switched off the digital recorder on his lap. "Exchange students, are you? Where from?"

"All over," Tegan said. "We're just visiting. Nyssa's a medical researcher; I'm just an old friend. Turlough here is still in school, though!"

Turlough shot her a sour look as the student hopped up and introduced himself eagerly. "Vevik Sanghu, sixth year, homeopathy. Was that blond fellow in the beige coat your advisor, then?"

"The Doctor? I suppose you could put it that way," Turlough said. "Which way did he go?"

"Your left, towards the BHR Centre," the young man said, pointing to a curving path skirting the grove from which they had just emerged.

"Thanks," Turlough said. "Nyssa, if you're so worried about running into someone, why not simply wait in the TARDIS while we— hey!"

"Rabbits!" Tegan's peculiar curse described the speed at which Nyssa had dashed off to the right towards a covered walkway leading between two buildings. "Nyssa! Wait for us!"

Turlough rolled his eyes. "I'm not chasing after her this time. And if she gets any moss on her, _you_ can apply the weed killer."

"Fat lot of help you are." Tegan said. She squared her shoulders and set off in a loose jog to chase Nyssa into the columned arcade. She failed to notice her friend pressed in the shadow of a pillar, half-hidden by the tendrils of ivy and blossoms encasing the stonework. Nyssa put an arm out to intercept, raising a finger to her lips.

"What now?" Tegan said. "You move pretty fast for an old lady."

"Hush." Nyssa drew her back into the shadows. "Look down there... carefully. Stay out of sight."

Pushing foliage away from her face, Tegan leaned out and squinted down the length of the walkway. At the far end, two figures were walking side by side, silhouetted against the bright sunlight beyond. "You mean the professor and that kid?"

"Look closely."

The older gentleman had his hands clasped at his back with jovial formality. There was a mannered elegance about him that seemed at odds with his plain black capelet and coveralls, which reminded Tegan of a professor's tweeds. As she watched, the pair slowed and halted, turning to face one another. The student was punctuating his speech with the enthusiastic gestures of a conductor. The older man leaned forward, listening gravely. His trim black beard and high, pale forehead were all too familiar.

"That man." Tegan clutched at her friend's arm. "No, Nyssa, it can't be."

"It is."

"The Master!"

Nyssa's gaze was riveted not upon their enemy, but on the weedy-looking youth. "Tegan, I need you to do something for me. Please."

"Oh, no you don't. I am not going back to fetch the Doctor while you face that psychopath alone!"

Desperation, helplessness and raw anger flared in Nyssa's eyes. "Follow them. Try not to be seen, but _protect that boy._"


	2. Flagrant Violations

"Doctor! There you are," Turlough said, puffing towards him across a broad circular plaza paved in a compass pattern of solar panels and flagstones. "We seem to have lost Nyssa."

"Mm," the Doctor said, peering through his glasses at a digital map. "Biohazardous Research Centre. Genetech, cryogenics, hydroponics, pharmaceuticals, pathology..." The directory glimmered within a flat, translucent post standing at the exact centre of the plaza, around which stood a cluster of five large pods the size of garden sheds.

As Turlough jogged up, the double doors of one of the pods slid open, disgorging four academics arguing loudly over some sort of "cognisance spectrum." A harried-looking student squirted between them and sprinted off. Turlough had to leap to one side to avoid being run over. "Oh, don't mind me, I'm just standing here existing," he called.

"But are you, boy?" said one of the faculty members. "That is the very question."

"Oh, don't start," said another.

"Excuse me," the Doctor said. "Can anyone tell me where the temporal—"

"Relative classification of awareness is sufficiently complex without bringing the fourth dimension into it," snapped an old woman with a face like a haddock.

"Even so," said one of her colleagues, "since mental processes fluctuate throughout the day, the time axis must be factored in."

The Doctor raised his hand to try again, then shrugged and stepped aside until the esoteric debate had wandered on its way. Giving Turlough a wry glance, he returned his attention to the directory, tapping a label with a fingertip. "Bioelectronics. Nyssa's specialty back on Traken, before she switched to infectious disease. But surely, even in a different department, she would've gotten wind of someone performing experiments in temporal mechanics."

Turlough cleared his throat. "This may come as a shock to you, Doctor, but I don't think Nyssa is telling us the whole truth."

"Really." The Doctor pulled out a coin, flipping it onto the back of his hand. He frowned and turned it over before heading towards one of the lifts.

"Really."

"Well, I'm certain she has her reasons." He pressed the call button and stepped back to skim the notices and advertisements scrolling past on the directory's default screen.

Turlough rolled his eyes. "Why is it that nobody trusts me, but when someone else starts acting suspiciously, nobody cares?"

"Don't care? Don't _care?_" The Doctor's voice shot up to a squeak before dropping back down, practically biting every word. "Have you any idea how long Nyssa and I travelled together while Tegan was back on Earth playing air hostess? Nyssa was... well, my ward, you could say, once upon a time. We worked well together. But now I must honour her wish to be dropped on some unknown planet without even a forwarding address. I may be accommodating, Turlough, but I don't have to like it."

"Unknown? But the TARDIS will have a log."

"Which she was programming the computer to wipe from memory the instant we leave here. I surprised her on the flight deck while she was setting it up."

"But why?" Turlough said. "What if she's still under the influence of... of... I don't know, that moss infection? What if the Mara's come back? What if the Black Guardian's trying to take her hostage? What if someone forced her to fly the TARDIS into that tachyon field?"

"Turlough. When you first came aboard, I trusted you with my life on several occasions. I was not mistaken. Are you saying I shouldn't give Nyssa the same benefit of doubt?" He pinned Turlough with a stern look, holding it for a beat after the lift doors opened.

"Of course not, but..." Turlough spread his hands, following him in. "If someone's getting at her mind, she may not be responsible for her actions. She could be in danger. At the very least, shouldn't you be keeping an eye on her?"

"Tegan's with her, isn't she?"

"Well, yes. I think so."

"_Q.E.D. _In the meantime, Nyssa's secrets are not our business. It's our job to—" he winced and reached up to pinch the bridge of his nose, knocking his glasses askew. "To—"

"Doctor!" Turlough caught his shoulders as he swayed. "Are you all right?"

"You can't feel that?" the Doctor said. "As if time just... shuddered?"

"I say," said a bright voice behind them, "is your advisor in need of a doctor?"

Turlough looked around. It was Vevik, the student who had greeted him earlier, propping open the doors with his foot. His brown face was creased with concern.

"Tachyon leak," the Doctor muttered. "Just... need to... _ah._" His face cleared. "Nothing to worry about, just a touch of vertigo. Do you happen to know if anyone here is conducting time experiments?"

"Time experiments?" Vevik said. "How do you mean? The elder care centre is adjacent to the main hospital, sir, if that's what you seek."

"Probably not, but thanks all the same. How do you do, by the way? I'm the Doctor."

"Why were you following us?" Turlough put in.

The young man pumped the Doctor's hand enthusiastically. "Vevik, homeopathy. I beg your pardon, Mr Turlough, but I wondered if you might not have heard about Hydra Pharmaceutical's product trials at the campus centre this afternoon. They are offering five thousand credits to volunteers."

"Splendid idea," the Doctor said. "There's a job fair taking place today, too, isn't there?"

"But, Doctor—" Turlough began, incredulous. Then he noticed the Doctor's eyes fixed on an old-fashioned paper flyer pegged by magnets to the back wall of the lift. _Terminus Medical Station, putting healing and care back into healthcare. Interns wanted._ "Oh. Oh, yes."

"Good lad. Vevik, I do appreciate your taking Turlough along. Don't let his mulishness fool you. A first-rate mind lurks beneath that sullen brow."

The medical student laughed. "I don't doubt it, sir." He gave Turlough a pleased, appraising glance.

Turlough raised an eyebrow and stared back. Was it his imagination, or was Vevik an unusually natty dresser among this philistine population? Unlike most of his peers, he eschewed coveralls for a neat linen jacket and well-pressed slacks.

The Doctor smiled at them in vague amusement. "You'd better hurry. Five thousand credits is over a month's pay in this sector, yes?"

"Yes, sir, and one semester's fees! That is why I am spreading the good news."

"Lead the way, then," Turlough said. "I'm very curious to learn what death-defying stupidity they want us to perform for our cheese."

"Meanwhile," the Doctor said to himself, poking a button at random, "I have nine floors to scour for a wayward time experiment. Why didn't I bring my time tracer?"

* * *

If Nyssa had asked her to swan dive off a radio telescope, Tegan could not have been more flabbergasted. "Tackle the Master alone? Are you crazy? As bright ideas go, that's right up there with croc wrestling!"

"Tegan." Nyssa's words came out strained, monotone: she was struggling not to raise her voice. "That boy. It's Lasarti."

"Who? Oh! _That's_ Lasarti?" Tegan gripped her shoulder. "Sit tight. You can count on me."

"I know I can." Nyssa gave her a tense smile. "Please, be careful, Tegan."

"I don't suppose you've brought a tyre spanner to lob at the Master's head? Right, here goes."

Looking both ways, Tegan squeezed through the curtain of vines and out to the exterior of the covered walkway. She found a dark, narrow gap between the colonnade and the adjacent building. Wrinkling her nose at cobwebs, she began to edge her way down the claustrophobic slot. The rise and fall of distant conversation urged her to move faster, but stealth demanded otherwise. Dry leaves and detritus littered the gutter, and the foliage outside the columns was unpruned. It took over a minute for her to draw near enough to make out words. She gritted her teeth at the Master's unctuous tones, which she had hoped never to hear again.

"...shamefully exploiting a young man with rare potential only because you lack family connections. But I serve a higher purpose: knowledge_._ In you, Lasarti, I see a fellow seeker. As your sponsor, I can supply you with the resources you need, provide access to academic institutions and their data. You will of course receive the top byline on any paper we publish."

"That's dreadfully decent of you, sir," Lasarti said, "and I can't thank you enough. I'd be on a ferry back home by now, if you hadn't swooped in to defend me. But how can I stick my name on the thing, when my proposal's already in the pipeline under my advisor's name? I'd be accusing Dr Vint Crane, chair of the IPA, of cribbing from an undergrad. Or, more to the point, proving the plagiarism charge that landed me in hot water in the first place. I'm grateful that you believe me, Professor, but the fact is, I should be chucked out by now. I don't really know why the committee listened to you."

"I may be able to reacquire your prototype from Dr Crane discreetly, so that you fall under no suspicion."

The student shook his head. "Forgive me, sir, but you've as much chance of pulling that off as I have of free climbing the obelisk to change the beanie on Dr Yi's statue."

"All will be arranged. Trust me, Lasarti. Serve me, and I can help you unlock the true secrets of dreams." The Master's voice began to take on a hypnotic resonance. "All the layers of the unconscious mind, the scars and forgotten shards of memory, open for your perusal..."

'Yeah, right," Tegan blurted from the shadows. "He's just gonna nobble your work like the last crook did." Turlough had compared her unfavourably to a crow with bronchitis, but in this case, the harsher the better.

Peering through leaves, she saw the gangly young man blink and straighten. She shrank from the Master's searching gaze, but there was nowhere to hide. At least she could take satisfaction in the stunned irritation that crossed his face before he recovered his poise.

"Good heavens. It's Miss Jovanka, isn't it? Well, well, what an unexpected pleasure. Do come out and say hello."

"Don't patronise me," she said, pushing through ivy and combing her hair with her fingers. Just her luck. She was finally getting to meet the guy who had married her best friend, and there were spider eggs in her fringe. "What are you doing here? Looking for slave labour among starving students, is that it?"

Lasarti's eyes darted between them, the corner of his mouth twitching upward.

"I was merely offering this impressive young man my personal patronage."

"How do you do, Miss Jovanka?" the boy said, extending his hand with an embarrassed grin. He looked about the age that Nyssa had been when they left her on Terminus. "Lasarti. Fourth year, psychology."

"Hi." She returned his handshake warmly. "It's really great to meet you. _You_, on the other hand..." She turned and looked the Master in the eye. "Shove off."

Lasarti blanched in mid-handshake. "Er."

"Miss Jovanka," the Master said, all smiles, "I apologise that I was not able to accept your application, but I fear that you continue to confirm my doubts about your academic rigour, your ability to engage in reasoned debate, and, indeed, in your mental stability. If you persist in stalking me, I may regrettably have to summon campus security."

"You do that," she said, folding her arms. "I'll wait right here."

"Or is it my new protégé you are stalking, perhaps?" he continued. "I'm not certain I should leave him alone with you. Just how do you come to know Lasarti?"

"Know him? We've only just met."

If the Master hoped to daunt her with the power of his voice, he did not have a chance to try. Suddenly, the building next to them erupted with an earsplitting din. The siren was magnified to painful levels by the echoes chasing one another down the vaults of the arched walkway. A fire alarm, Tegan guessed, hunching her shoulders against the clamour. She had a good idea who had pulled the lever.

"That's my residence hall!" Lasarti said.

"A prank, no doubt," the Master said. "Do not trouble yourself."

"Pardon me, sir," he said. "I'm terribly grateful and... got to go. Your office hours— tomorrow— stop by—" He was already running.

Tegan threw herself forward, jostling the Master and sending him sprawling into the ivy as he turned to follow. "Oops!" she said, sprinting past. "Sorry about that, Prof!"

Lasarti was a beanpole of a boy, angling between gaps in the crush of students streaming out the front doors of the building. "Oi!" called a girl. "Las, are you deaf?" He ignored her and the insistent wail of the alarm, hurrying inside and pelting up the stairs. Tegan trailed him doggedly, thanking the Doctor for a year of training in this department. Two flights, three— why did student residences never have a lift? — and he veered off towards a door halfway down the broad landing. Fumbling for a key, he opened the door and darted inside.

Tegan followed on his heels, shutting the door behind her. The noise in here was only a little less deafening. She found herself in a narrow but neat single. A planter overflowing with large pod plants blocked the window. Extra light filtered through frosted glass orbs embedded in the walls. There was only a moderate jumble of books, data chips, clothes and bric-a-brac, but a male student's pad was incomplete without at least one pair of underpants on the floor.

Lasarti sat down on these and peered under the shelf bed. His movements were slow, careful and unthreatening, unlike the cacophony outside. In a soothing voice, he began to single a playful, old-fashioned jingle that reminded Tegan of vaudeville matinee songs back on Earth:

_If I can't be the Jack of your heart,_

_Then I guess I'll be a Joker_

_Because I like..._

_your..._

_smile..._

"Hey, that sounds like an Earth song," Tegan said. She wondered idly what the TARDIS' telepathic circuits had translated into playing cards.

"Earth?" he said, distracted. "I always thought that planet sounded terribly dry. No, it's one of my grandma's show tunes. She was a performer down on the south shore. Shh, Effie, come out, love, sshh, it's all right. Come by, now." He hummed the tune again, wiggling his fingers under the edge of the bunk.

Something white and fluffy shot past his hands. Tegan dropped by instinct to block the exit, although the door was already closed. The cat-eared, bipedal furball banked off her shins. "Whoa, little fella, I'm not gonna hurt ya." It hopped out of her grasp and spun around, whisking back under the bed. Tegan removed her high heels and crouched beside him. "Have you got a carrier or something?"

He nodded, picked up a pillow, unzipped the cover and handed it to her. "Thanks. Here. Don't worry if she nips; she's been fully inoculated." On that not entirely reassuring note, he lay down on his side and resumed singing to the beady eyes peering out at him. At length, the small creature's snout edged out. Lasarti made a sweeping grab and cuddled Effie to his chest, coaxing and stroking it before tipping it gently into the bottom of the pillowcase. Tegan zipped it shut as tiny paws began scrabbling at the fabric.

"There. Contrary to rumour, dust bunnies have not, in fact, formed a breeding colony in student housing." Reclaiming the wriggling satchel, he held it under his half-cloak. "Can you get the door, please?"

Tegan nodded, wincing as they stepped back into the blaring hallway. Lasarti had his hands full trying to keep hold of his small bundle. Tegan preceded him down the stairs, partially shielding him from view. This was just as well. A janitor was blocking the first floor landing, deactivating the fire alarm. The racket stopped just as Tegan did, trying to figure out how to shepherd Lasarti past her without giving the game away.

"Why are you two still here?" the woman snapped. "The fire alarm's been ringing for ten minutes."

"Sorry, ma'am, we're just leaving," Lasarti said, tugging furtively at the front of his cloak.

"Don't bother." The janitor flapped a hand wearily. "False alarm. But next time it may not be. Word to the wise, kids. It's less embarrassing to run outside in your dressing gowns than to die stark naked and become a campus legend. Good day."

Red-faced, Lasarti huddled against the wall until she had gone down, then retreated upstairs just ahead of the incoming wave of residents. Tegan followed him back to his room, where he decanted the squirming creature onto the mattress. Tegan caught a brief glimpse of its black button eyes and pointed snout before it hopped down and darted back under the bed.

"Er... well, thanks again, Miss Jovanka." His quizzical expression had returned.

"Glad to help," she said. "She's not the first violation of the housing policy I've had to rescue during a fire drill."

"So I gathered." He grinned, relaxing. "Flagrant Violation, to be precise. F.V., Effie, for short. She might come out once the noise outside quiets down."

"Cute little thing. Looks like a powder puff crossed with a wallaby."

"A what? Is that an exospecies?"

"Never mind. Look, can we start over? You must think I'm crazy, popping out of the bushes like that."

"Well, I was a little taken aback. Are you sure you haven't mixed up Professor Daskalos with Dr Crane?"

"It's a long story. I'll tell you up front, though, I'm not any kind of student or scientist at all. I'm just a space tourist. Which sounds even more barmy, doesn't it? Anyway, that Daskalos guy has hurt a lot of people I care about. I hate seeing him sink his claws into someone else."

"Subjective realities, exhibit A." Lasarti's brows knitted. "Could you be a little more specific? No, wait. Look. I appreciate your going out of your way to tell me this, but I'm going to be late for lab. Naughty boy can't afford any more demerits on his record. Could we meet for coffee afterwards? Er... assuming they drink coffee where you come from?"

"Sure!" Tegan said, retrieving her shoes. "I'll have you know my planet invented that sludge. Where and when?"

"The Chirurgeon Café in an hour and a half?"

"Right! I'll see you then." She reached down to scratch the twitching nose peeking out from under the bed. "Hi to you too, puffball. Stay put." Standing, she let herself out, careful to block the door with her feet. She wondered whether a pet violation was sufficient grounds to have Lasarti expelled. It might be preferable to whatever the Master was planning for him.


	3. The Master's Daughter

"So, Turlough," Vevik said, charting a course between walkers and riders on the university's main service road with an ease that Turlough was appalled to find he could still manage. "What is your institution, if I may ask?"

Turlough snorted. "Tegan was pulling your leg, I'm afraid. Or rather, mine. I was in Brendan School back on Earth, but I'm... well, let's just say that I'm exploring other options. Of which I find plenty, travelling with the Doctor."

"Doctor." The young man frowned. "Of what? He spoke of time experiments, but I cannot think what he meant by that."

"Join the club. We were dropping off a friend here, when his instruments picked up some bizarre readings that ought to have come from a physics lab, not a medical research facility. The Doctor's trying to pinpoint the source. Meanwhile, the rest of us are stuck until he's satisfied his scientific curiosity."

"So, you're not in medicine." Vevik drooped. "But a student of sorts, you say?"

"Of sorts. Travelling with the Doctor, one learns all manner of things," Turlough said. "Like how many different ways the universe can kill you," he added under his breath.

"I beg your pardon? Ah, here we are!"

The student centre, like the rest of the campus, was obviously built for a warm if rainy climate. The ground floor was open on all four sides, providing access to a large atrium. The exterior sported rolled-up awnings that could be extended to cover outdoor seating during a downpour. Cafés and shops occupied the building's corners. Vevik guided Turlough through the beehive bustle into the atrium, where booths had been erected between support columns. Queues snaked to and fro, turning the spacious open area into a labyrinth. Vevik settled into the back of one of the longer queues.

"It looks like word of the five thousand has spread," he said, eyes twinkling. "I shall hold our place, Turlough, if you care to look around."

"Thanks," he said, privately cursing the Doctor for sending him on another boring reconnoitre. "I'll do that, if you don't mind."

He knew what the Doctor feared. If Terminus had sent representatives, there was a chance that Nyssa might run into herself. In fact, that might be the very reason she had been acting so dodgy. Suspicious as Turlough was of everyone and everything, he had come to the wry conclusion that Nyssa had zero capacity for scheming. There was something terribly out of joint when she started behaving like him.

He soon found himself falling into a walking torpor, lulled by glitzy holographic displays over high-tech kiosks. Which of these pharmaceutical corporations, he wondered, had engineered the virus that Nyssa was trying to cure? Turlough had nearly abandoned his search when he spotted an out-of-the-way table staffed by a solitary young man with enormous hair. He was fielding questions and waxing enthusiastic about patient care and worker opportunities. While his white scrubs looked professional, his employer clearly needed to establish stricter guidelines concerning mullets.

Elbowing his way to the front, Turlough found himself at a pop-up booth decorated with simple 2D posters that had been lost amidst the commercial industry's high-end displays. The table's surface offered a quaint spread of old-fashioned paper pamphlets. He almost expected to see a photocopied flier fringed with tear-off phone numbers.

He selected a booklet at random and turned it over. Sure enough, the back cover featured a biographical blurb and photo of a smiling Nyssa, looking nearly as pretty and young as he remembered from their first encounter. _Little nun, _he thought wryly, recalling the Doctor's brutally honest barbs while under the Mara's spell. Soft focus limned her face with an angelic aura, but close inspection showed a darker story. Image processors had done their best, but her shadowed eyes and gaunt cheeks suggested that her first years on Terminus had been difficult. Strange to think that this younger, haggard Nyssa was still out there somewhere.

"Excuse me," he said, interrupting a lively conversation about the prospects of a Lazar's vaccine. "Is Nyssa here today?"

The booth attendant's shoulders rose and fell in a resigned sigh before he donned a plastic smile. "The Director is on Terminus Station," he said. "I'm sure she'll be very pleased at your interest in our care facility and cutting-edge research."

Turlough laughed, divining the man's unspoken thought. "I'm not trying to get her autograph. She'd bite my head off. I'm one of her old chums who accidentally stranded her on Terminus. Good to see she's made the best of a bad job."

"I assure you, sir, our station is an entirely different facility from the poorly managed hospice that you remember," the man said. "It has been replaced with a _hospital._ Our patients receive one-on-one care, counselling and physical therapy—"

"And she's probably rescuing sick puppies and orphans on the side, making you wash behind the ears and eat organic sprouts. Yes, I know." Sensing that he was overstaying his welcome, Turlough held up the pamphlet. "May I keep this?"

"Yes, of course," the man said hastily. "If you'll excuse me, sir." He turned back to his audience. "The Director has gained a certain notoriety for her part in dismantling the powerful Terminus Corporation. Their paid attack journalists have painted an unflattering caricature. In fact, we have difficulty prying her out of the lab... What was your question, again?"

_If it's no longer a leper disposal service, then why in blazes did you keep the name Terminus? _ Turlough had never dared to ask Nyssa, and he doubted he would get a straight answer here.

He ambled back to rejoin Vevik in the queue, idly skimming the booklet. Tegan might be interested in the photos of the new facility. It was sterile and institutional, but at least the staff now dressed like doctors rather than gladiators. Also, the skull decor had been replaced with art deco light panels, which to Turlough's mind was barely an improvement. The pamphlet concluded with a feel-good piece about the Garm, formerly a slave, now head of the children's ward. Turlough wondered whether it minded having its doggy likeness used as a mascot.

"Terminus?" said Vevik. "Ah, that is a sad story. I have heard terrible rumors."

"Most of them years out of date, I expect," Turlough said. "The pay's not bad, for a starting stipend."

"That is odd," Vevik said. "I had heard that the employees were slaves in all but name." He peered at Nyssa's portrait. "Now, where have I seen this person before?"

"Maybe at a symposium," Turlough said vaguely.

"No, I recall it now. My father is an attorney, and he followed news of the case. She spoke for the prosecution."

"Speaking of trials... Vevik, this drug trial we're queuing for. What exactly are they paying us to do? Or to ingest, more to the point?"

"It is Stimsi," Vevik said. "Ah, they do not sell in your home system? Very popular among medical students, an alertness aid. But there is no need to worry, Turlough. There are no synthetic molecules. It is all refined from living materials."

"Ah, yes. 100% organic, just like arsenic and salmonella."

"Indeed," Vevik said, smiling. "You must have studied organic chemistry and its application to dining hall cuisine."

"I try not to," Turlough said. "So, assuming this new, improved Stimsi doesn't poison us, I don't suppose you could recommend a decent café? I don't relish the thought of a school canteen."

"As to that," Vevik said, "if you do not think it forward, I should be most pleased to invite you—"

A woman's voice over a loudspeaker cut through the hubbub. "Welcome, welcome, to Hydra Pharmaceuticals' Stimsi Sweet Challenge! Step right this way, to discover the new great taste that turns nutrient paste into Orion ambrosia!"

Turlough groaned. "A vegemite taste-test? Slay me now." He suffered himself to be herded along with Vevik into a roped-off area. His spirits brightened again when he realised that tables were interspersed with putrid outcroppings of modern art and potted shrubbery. There were plenty of discreet hiding places in which to dump unknown substances.

Five thousand credits were, after all, five thousand credits. He hoped this planet's banking system would recognize his identity and allow him to upload them to his secret account. For all the aggravations of travelling with the Doctor, compound interest made some of the risks worthwhile.

* * *

Nyssa slipped out the back of Lasarti's hall of residence and plunged into the chaotic flow of students for camouflage. The confident stride of a campus native made it easier to blend in. Nevertheless, she drew a few puzzled looks as she forded the crush. It was hardly customary for a faculty member to be kitted for deep space exploration. She needed to stop by the TARDIS and change before she drew the attention of unfriendly eyes, or even friendly ones. First, however, she had to find Tegan and make sure she was safe.

She emerged onto the sundial quad and began watching for familiar gaits. Lasarti, she hoped, was in his room securing the ridiculous pet that he had smuggled through Terminus' quarantine six months before she discovered it. She dared not let him catch sight of her. There was no telling what might happen if they met now, a year too early and with decades of living etched upon her skin.

"Excuse me, ma'am, are you lost?" called an orderly supporting a frail-looking patient.

"I'm fine, thank you," Nyssa said, averting her face. "Have you seen a young woman pass this way? Offworlder clothes, short-cropped hair, shoes with heels raised on points."

The orderly blinked. "I haven't noticed any such person, but I haven't been paying much attention to the students. Mz Rotisan, did you see this offworlder?"

"Kids these days," the patient wheezed. "Traipsin' around in spacesuits like Captain Zoom. Where's your helmet then, son?"

"Thank you very much," Nyssa said. "Good day."

There was no sign of Tegan. After pacing the perimeter of the quadrangle three times, Nyssa warily returned to the covered walkway where they had parted. No sign there, either. Unfortunately, her attire kept drawing more curious glances. A pair of students walking towards her were whispering to one another and avoiding her eyes. She gave them a curt nod, slowing her steps until they passed. She was about to duck into the vine-choked archway where she had taken refuge earlier when the person she had been dreading stepped out of it. She recoiled, but it was too late.

"Nyssa." The Master spread his arms, a welcoming gesture that made her heart ache. Not only his face and voice, but his every movement was a grotesque pantomime of her late father whose body he had usurped. "Nyssa, my dear child, it's been too long. Let me see you!"

"Stay away," she said. "In fact, you should leave Zarat at once." She palmed a small capsule from the wrist-guard of her suit, making no attempt to conceal the motion. "You don't belong here."

"So inhospitable, my dear, and to your own flesh and blood. I fear the Doctor's influence has begun to taint your natural sweetness." He frowned as he came forward. "Goodness me. What has he done to you? Time travel has not been kind to you, my dear."

Her age mystified him, she realised. He had last seen her travelling with the Doctor and Tegan as a precocious teenager. "You're trying to pretend that you're not responsible for the tachyon surge we passed through on the way here?"

"Tachyon surge? I don't know what you're talking about." His musical voice took on a sudden insistence like a whipcrack. "Where is the Doctor?"

"I don't know." Even braced for it, she found herself struggling not to blurt out a straight answer. "Playing cricket, I expect."

"Obstinacy does not suit you, my dear, any more than time's ravages."

She gave him a contemptuous look. Her real father had always been proud of her stubbornness, even when it was arrayed against him.

"Come, come. This is no fit place for a reunion. Why don't you accompany me back to my office? I'd be delighted to introduce you to my new protégé, Lasarti." His scrutiny and voice sharpened. "Come, Nyssa. You will obey. You yearn to obey me, daughter..."

The effort of blocking out mental commands made it difficult to guard facial expressions. It was impossible not to grit her teeth when he purred Lasarti's name. The Master's eyes glinted in triumph. He still looked puzzled, but there was a cunning calculation in his eyes now that she disliked.

"Leave Zarat," she said again. "I can expose what you're doing here, or resort to less civil means if I must. That body you're wearing is vulnerable. And there are some pathogens that can overcome even Gallifreyan immunity. Spectrox, for example." Oh, it ached to know that, and not to be able to warn the Doctor.

"Why, my little flower has developed thorns," he said, laughing. "Leave Zarat? You are the intruder, while I am a distinguished adjunct faculty member. Perhaps I should summon security and have you questioned for making terrorist threats. No, better, I've been looking for volunteers to test Lasarti's dream interface. Shall we walk together, you and I, in a vision of vanished Traken— oh, yes, you belong here, Nyssa, amidst the cloying scent of flowers, the decency, the _lassitude—_ or will you yield to me the secrets that the Doctor has shown you since you left my side?"

"You... you were Professor Crane." She spoke with difficulty, holding onto indignation for Lasarti's sake as a talisman against that cruel, seductive voice. "He never existed. And now that his academic theft is about to come to light, you've changed identities again."

"Don't be silly, girl, of course he existed. His mirroring-therapy android has proved invaluable to me." His smile was cold. "No doubt Dr Crane will have much to answer for, if he ever returns from his... extended sabbatical."

Nyssa shuddered inwardly. She felt no charity towards the man who had nearly ruined Lasarti's career before it began. All the same, she had no wish for anyone to die at the Master's hands. "As will you."

"So," the Master said, taking another step closer. "You know about the late Vint Crane, do you? Then I suppose you and Lasarti must also be acquainted. _Intimately_ acquainted."

She suppressed a wild urge to strike him. "Stay away from him."

"What, and miss the chance to meet my grandchildren?"

He was goading her, stoking her anger until it became not armor but a wedge to cut through her mental barriers. Her focus was beginning to blur, fear and fury chasing themselves around her brain. _Not Neeka. Not Adric._ In her mind's eye, she beheld a captivating image of her beaming father, his hands resting on her children's shoulders. Their young, upturned faces tilted towards him in glowing devotion. "No!"

The Master blanched as if her furious mental shout had scored a hit. And then, faintly, she heard her father calling her name.

_Nyssa? Nyssa, Nyssa, help me..._

The vision changed: her father lay huddled on his side in a colourless void, his face contorted in anguished appeal. _Please, take my hand... Nyssa, I know you are there..._

It was Tremas' voice, weak with fatigue and horror and hopelessness, a feeble plea reaching out to her from across an infinite chasm of space and time. Had some remnant of him survived the Master's possession, a prisoner caged deep within his own mind? She took an involuntary step forward. Every straining fibre of her soul yearned to answer. Her father's doubled features— aged and despairing, sleek and exultant— swam before her eyes. Gloved fingers began to steal around her wrist.


	4. Dire Secrets

Nyssa had just enough willpower left to snap the capsule, fling it to the ground and whirl away as it went off. There was a silent flash. The entire length of the arcade was lit in a searing white light. Shrieks and curses burst out from somewhere beyond the Master: a few unlucky bystanders must have been caught in the glare. _No permanent retinal damage,_ the tiny rational corner of her brain reminded her. _Don't look back._

She ran. There was no help for it this time. Heads began to turn as soon as she sprinted back into the open quad. She did at least have the presence of mind not to head straight for the TARDIS, but to dodge behind another building instead. Instinct and adrenaline took over. She was fleeing towards her laboratory, even though it would be another ten years before its foundations were laid. She wove between trees, bypassing pedestrian-clogged walkways, listening for the sound of pursuing footsteps.

There. A swatch of beige and red. She veered towards it and did not slow down, feeling a childish stab of relief as the Doctor's arms swept around her. Laughter came a moment later, when she had to catch him before they both tumbled to the pavement.

"Nyssa!" He swung her behind him, staring past her. "What's wrong?"

"Someone... recognised me," she said. "Had to get away before... temporal paradox..." Her thoughts were scattering like Tegan's rabbits. Her very brain felt quivery, flailing like a bird trying to free itself from netting. Lasarti's voice rose and fell in the back of her mind, reassuringly professional. _Mental assault, subjectively the same as physical... often a delayed response... perfectly normal, while the unconscious assimilates the trauma... _She closed her eyes and propped her forehead against the Doctor's cricket jumper, trying to shake off the jangling horror of the Master's last words. The scent of celery was comfortingly familiar, if peculiar.

"Steady." The Doctor gathered her gently and guided her towards the nearest tree, helping her to sit with her back against it. "Deep breaths. Are you being followed?"

"I don't think so," she said, letting her face drop into her hands. Little by little, ordinary sounds and scents came back to her. A kit-bird's call, a bittersweet echo of Traken's crested avar. The susurrus of needles rustling on the light breeze. A faint whiff of camomile and thyme, small creeping flowers crushed underfoot by students taking shortcuts. A fainter tang of salt. Chattering voices, the quick crunching footsteps of cross-campus trots as students hurried between lectures. Home_._

She let out a puff of breath. "Thank you, Doctor. I'm all right. Blinovitch Effect. I had no idea it was so disorientating."

"Hm." His wry smile was fond. "Despite my corrupting influence, Nyssa, you've never gained the faculty to lie convincingly."

"I said I'm fine. Just... I need a moment."

The Doctor folded his arms across his knees, waiting in a crouch beside her. As she struggled to find something to tell him that would not simply raise more questions, he launched into amiable patter. "You know, Zarat Medical Academy is a remarkable institution: green spaces, plentiful trees, medicinal herbs in the lawns, pavements to filter and recycle rainwater, and not a single architectural monstrosity apart from those lifts resembling rubbish compactors. The atmosphere reminds me of the ancient healing sanctuary of Epidauros on Earth. The sound of wind through evergreens is most characteristic. There's even a sea a few miles off, isn't there? I can see why you relocated here."

She raised her head, troubled. "Doctor—"

"I think it's time we stopped pretending, Nyssa. You didn't want me to know where you were going, and a powerful force tried to stop the TARDIS from bringing you here. Now someone's attacked you. It all adds up to the same thing. You must tell me what."

"But it doesn't. At least, not that I can see. And I would never have brought you here if I'd realised the danger." She felt like a pawn embedded on the far side of the chessboard, hemmed in by a shrinking noose. If only she could confide in him! But if she did, the Doctor would surely go charging off to confront his old nemesis. Then it was a simple matter of the Master planting Lasarti in his path, so that they met now instead of later when the Doctor's very life hung in the balance, and the timestream would be altered. Was such a minor change enough to jeopardise his regeneration? She didn't know, and she dared not ask. Somehow, she and Tegan must queen themselves and castle the Doctor before he was checkmated.

"What danger? Nyssa, you have to tell me." His voice was soothing, insistent.

"Don't you start. I've had quite enough of people trying to get inside my head for one day!"

He rocked back on his heels, forehead knitting in deepening concern. "I think we ought to get you back to the TARDIS."

"Yes, I... I need to collect some things. Doctor, I'm sorry." She stretched out her hand to him in apology. "After all the psychic attacks I weathered while travelling with you before, something like this ought not to faze me."

"Fifty years is a long time. I don't suppose you've had much cause to practise the meditation techniques I taught you." He took the gesture for a mute request. As he lifted her to her feet, his fingers abruptly tightened under her elbow. "The Master? It's the Master, isn't it?"

She couldn't lie, not about this. Still she hesitated.

"Isn't it? For goodness' sake, Nyssa, stop fighting me!"

"Yes." Eyes downcast, she allowed him to begin leading her towards the TARDIS. "Posing as a professor."

"And you thought to shield me." He raised his eyes skyward. "Sometimes I wish you all had Turlough's sense of self-preservation. "Where's Tegan?"

"Safe, for the moment. She's with my— with a colleague of mine. She's on her guard. What about Turlough?"

"Student centre, some kind of job fair. You didn't come here recruiting on this date, did you?"

Startled by the mundane question, she needed a moment to collect her thoughts. "No, I'm still mired in paperwork back on Terminus."

"Good." He marched faster as his mental wheels churned. "The tachyon emissions are coming from underground, presumably somewhere in that biohazardous research complex. What's the Master's involvement? Did he drop any hints?"

"I'm not certain. When I challenged him, he claimed to know nothing about a tachyon explosion. I almost think he was telling the truth. All I know is that he is taking a very personal interest in my past."

"Then the sooner you're safely inside the TARDIS, the better."

Spotting the blue door peeping through the trees ahead of them, Nyssa slowed. "Doctor, wait. I've been less than frank with you, because there's something in my own past that impacts your future. Every moment we're here, we risk altering that timeline by setting up a contradiction. It could threaten your very existence. That's what the Master is after. I'm sure of it."

"A temporal paradox?" The Doctor relaxed, despite the dire warning. "Well, now, that makes things somewhat clearer. I was trying not to be offended at your attempts to give us the slip."

"It's not how I wished to leave. I didn't know what else to do."

"If I weren't peeved at being left in the dark, I'd applaud you for a Time Lord's discretion." He sighed. "So, what do you suggest? Leave Zarat to avoid playing into his hands? We may be able to bypass the brunt of the distortion by going back in time, or sideways, as you pointed out."

"No!" She wrestled fear aside. _Lasarti, Neeka, Adric._ She might be a pawn, but at least she was aware of the chessboard. "No. Leaving won't stop him. I must see to that. Tegan's helping me."

"Tegan!" The Doctor pulled up short, voice rising an octave as his temper began to fray. "_Tegan?_ That is utterly out of the question. You of all people should have more sense! Whatever he did to you—"

"Mind control. He failed. Doctor, I can defend myself."

"And Tegan?"

"Perhaps you underestimate her." Nyssa squared her shoulders. "Look, I'm not happy about bringing her into this, but you know the Master prefers to prey on isolated victims. She isn't alone. And I'm going back to join her, just as soon as I've collected a few things that may help." She looked up. "Believe me, I'm not taking this lightly. He terrifies me. But one of us has to stop him, and this time you can't, so I must."

They had reached the TARDIS, where he halted and turned to loom over her, expression stark. "Nyssa, not to put too fine a point on it,_ you cannot regenerate._"

"We're of more use to him alive than dead." She recognised the shadow that had fallen across him. She had named her son for the same ghost. Feeling oddly maternal, she reached up and brushed a stray lock out of the Doctor's eyes. "And regenerations can fail."

His face went blank. "Ah." Propping his arm against the doorframe for support, he raised his head and gazed out through the trees, visibly collecting himself. "I deeply appreciate what you're trying to do, Nyssa, but you cannot change history. Not even for me."

"No! Oh, no, Doctor, that's not what I meant. The Master is the one trying to change it. He's the one who won't care if he triggers a temporal paradox while altering... what must be." She closed her eyes, remembering her last glimpse of the Doctor's shining, dying body falling away into the ghostly chrysalis of the Watcher. "For what it is worth, it's not only your own future in the balance." She felt the chill truth of those words as she spoke them. If the Master could not suborn Lasarti to his own ends, the easiest way to stop her from helping the Doctor with her husband's machine was to eliminate its inventor. "Please. We're both walking a very delicate line, but at least I know the future's proper course. I'll do my best to hold it steady. You can't, not unless I tell you your own future, and that in itself may initiate a paradox."

The Doctor lapsed into silence. She heard the soft click of the key in the lock. She opened her eyes to find him looking down at her with an unfathomable expression.

"Sometimes I wish you had two hearts," he said. "But you do, don't you? The other is Tegan. You'd best be getting back to her. While I... continue hunting for temporal anomalies. Are you sure you don't remember any unexplained happenings in the BHR Centre?"

"No... wait, there was something." She glanced over her shoulder. "My virology lab took over a space formerly occupied by a cryogenics R&amp;D project. I don't know the details, but I gather they shut down after a serious accident landed someone in hospital."

"Frozen time... of course." He leapt into motion. "That's it! Nyssa, look after Tegan. I expect to find both of you back here safe and sound." He was already striding away, preoccupied, steps purposeful, all but running now that he had a bearing.

"I promise," she called, smiling faintly at his abrupt exit.

Pushing into the console room, she picked up the medical canister she had left by the hatstand and carried it with her into the warren of endless corridors. The TARDIS wardrobe was her first stop. For once, she had too much on her mind to be distracted by browsing its treasures. She surfaced with a pair of nondescript coveralls and a short cloak that would blend in with casual campus attire. She was not sanguine about shedding the minor protections offered by her scout suit. On the other hand, biohazard film and light armour were of little use against the Master's modes of attack.

Next, exigency trumping etiquette, she ventured into the Doctor's room to borrow his Little Mind's Eye. The blue crystal pendant was still lying on the shelf where he had tossed it. He had picked it up as a replacement during their last eventful trip to Manussa, where they had once again fought off the Mara's psychic possession. The crystal was meant as a focus for deep trance and dream-states, but it might bolster the mind's resistance, at least a little.

She had wasted too much time. There was no telling what the Master might have done to Tegan by now if she had been caught. Nevertheless, Nyssa made a quick detour to the ship's lab to drop off the antigen container and pick up an ion bonder. Back on Traken, she had discovered by accident how to miscalibrate the tool and create an effective stun beam at close range. Unlike the Doctor, she had no compunctions about arming herself with non-lethal weapons. Usually she honoured his wishes, but not now. Not with every single person who was precious to her under threat.

She nearly crashed into Turlough waiting outside, slouched against the TARDIS door. He grabbed her by the shoulders, releasing her just as quickly. He had always been a little skittish in her presence, even when she was young. "There you are! I've been trying to find you. Bad enough when the Doctor runs off—"

"Turlough, I'm sorry, but I'm in rather a hurry."

"Fine, fine," he said. "I'll just toss out this suspiciously free product sample, then, shall I? Someone's handing them out to the students by the crateful. But I'm sure it's nothing important." He dangled a foil blister pack between his fingers.

She glanced at the small packet. "Stimsi? It's a synthetic caffeine enantiomer. A common alertness aid among nurses and researchers."

"Ah, that explains why some pharmaceuticals megacorp is offering them five thousand credits for a taste test."

"What? But that's like paying humans to drink alcohol!"

"Exactly." He held it up, reading the label with exaggerated smarm. "'STIMSI SWEET, a new great taste for gel or paste.' It's been reformulated to make nutrient drinks palatable, or so the promoters claimed. I wouldn't know. I prefer not to imbibe green glow-in-the-dark ectoplasm."

"They were adding this to hydromel?" She took the blister pack, frowning. "I really must go, but I'll run an analysis on this as soon as I can. Thank you, Turlough."

"Hey," he said. "I don't suppose you know where the Doctor is?"

"He's investigating the cryogenics lab." She pointed. "Turn left as you exit the TARDIS, and—"

"All right." Turlough waved her off. "That underground bunker, yes? I hope you have a sound reason for dragging us here, Nyssa. Wandering around alien school grounds is precisely not my idea of a good time."


	5. My Best Friend's Bloke

The Doctor, meanwhile, had retraced his steps to the Biohazardous Research Centre. The roof-plaza's solar panels, rayed pattern of flagstones, and scattered planters would have made a whimsical sculpture garden, were they not overshadowed by the ugly lift bays. Below ground, the complex was a soulless warren like any other. At least the designer had tried to ameliorate harsh lighting and putty-coloured walls with light wells and sealed panels of falling water. Heavy bulkhead doors in the joints between corridors hinted at robust quarantine procedures.

Threading the maze, the Doctor eavesdropped on conversations and perused notice boards to take the vital signs of a thriving, well-funded research facility. There were no obvious warning signs of megalomaniac scientists. However, he knew better than to take Nyssa's association with them as a foolproof indicator of scientific integrity.

At last he reached a pair of heavy doors, sealed tight with pneumatic hinges. They hissed open in response to a hand-activated motion sensor. Warm, slightly damp air lifted his hair as he stepped through. Descending a shallow metal ramp, he found himself on the floor of a large, hangar-like chamber.

Its ambient temperature was warmer than the rest of the building, despite banks of air conditioning vents and fans in the exposed ceiling. Against the left-hand wall stood a row of opaque glass columns, their exteriors coated with frost. More tanks of various sizes and shapes were scattered in islands across the floor. A long counter spanned the right-hand side of the room, partitioned into desks, computers, shelves, tool racks, and bins of electronic oddments. Two of the workstations were occupied by a girl and a youth of indeterminate gender, both of them engrossed in tables of figures flowing past on large glass displays.

Elaborate metal scaffolding closed off the far end of the room. Its rigging supplied a web of cables flowing into a stout grey metal canister, chest-high, banded by hoops of a dark, polished material that sparkled like volcanic basalt. Beside it, perched upon a stepstool, a dumpy, middle-aged woman was adjusting dials and connections. To judge by her intermittent swearing, the procedure was not going smoothly.

The Doctor began to explore, footsteps masked by the whirr of fans and machinery. Taking a handkerchief from his pocket, he rubbed away frozen condensation from the glass of a nearby cryogen tank. He peered inside and raised his eyebrows at the grisly shapes within. "Morbius," he muttered under his breath, hoping the assorted organs were synthetic rather than harvested. With that sobering thought, he moved on, perusing whatever notes, diagrams and scribbles were lying on work surfaces or pinned to walls and equipment.

One of the students gave a yelp and turned, startled by the Doctor's moving reflection on hir workstation's glass screen. "Professor Xertes! A visitor."

"How do you do?" he said, doffing his hat. "I'm the Doctor."

"_The_ Doctor? Is that supposed to be some kind of joke?" the girl at the other terminal said, not looking up from her figures.

There was a curse and a crackling pop from the far side of the room. The Doctor's smile turned sickly for a split second as he reached for the nearest stable surface to steady himself.

"Who the devil are you, and what are you doing in my laboratory?" bellowed the professor. She made a minute adjustment with a needle-nosed tool and snapped the access panel closed. "Doctor of what? Trespassing?"

"Among other things," he said, strolling towards the machine that was obviously the cause of his headaches. "I beg your pardon, but my curiosity was piqued when I heard that a cryogenics expert was moonlighting as a temporal physicist."

"Does this Doctor of Snooping have a name? An accredited institution? A shred of identification?" Xertes' voice rattled around the room like the percussive sounds of an ancient magnetic resonance scanner.

"Doctor John Smith," he said. "Academy of Gallifrey, although it's been some time since— _ow._" He winced and pinched the bridge of his nose. "I say, could you check the alignment on your tachyon beam collimator? I'm afraid you may have some leakage."

"Gallifrey?" She hopped down from the stepstool, smoothing back tufts of salt-and-pepper hair. "Shards, that's all we need. Hathli, Chrys, save and shut down. I'll see you tomorrow, first period."

"But, Professor Xertes—"

"Immediately, please," she said. "I need to speak to this man alone."

"Yes, Professor." The young people gave him curious looks as they filed out. The Doctor nodded pleasantly to them as he drifted towards the imposing scaffolding.

"Now, Jonsmith," Xertes said, following her disciples as far as the door and sealing it behind them, "I'll bid you a hearty welcome if you're here to observe or assist. But I doubt it."

"Just Doctor, if you don't mind," he said. "And the Time Lords didn't send me, I can assure you. I'm an independent, so to speak."

"Independent?" She snorted. "From what little I've been able to uncover about those secretive bastards, the Time Lords exercise their ability to traverse all of time and space by sitting on their desiccated posteriors and presenting a stiflingly united front. I made the mistake of trying to contact Gallifrey ten years ago, seeking a scientific exchange."

"Oh," he said, with some sympathy.

"Oh indeed. By the time I'd returned from the hyperspace communications centre, all my notes had vanished along with my original mockup of that." She nodded towards the squat drum occupying pride of place. "It's taken me eight years to recover."

"They can be rather protective of space-time integrity," he said with an apologetic bow.

"It's called a corporate monopoly. And I have not the slightest interest in time travel. All I'm trying to do is come up with an alternative to long-term suspended animation that doesn't degrade tissue."

"A stasis field generator." He gestured towards the device. "May I see it?"

"First tell me what you're doing here."

"Well, as I was saying, your device's shielding may be compromised. I crashed through a severe temporal distortion on the way here. Something is releasing vast amounts of tachyons into the time vortex. Is there anyone else on Zarat engaged in time experiments?"

"Not that I know of." Her eyes narrowed. "All right, be my guest. But if you try to tamper with anything—"

"I'll be as discreet as the plashing moonlight, as Actaeon said to Artemis. Yes, I do understand."

Tense and sceptical, she monitored his every move as he began circling around the stasis field generator. He poked and sniffed, listened and prodded, yanked a finger back from live current, and dropped to one knee to examine the manifold at the base of the drum. Finally, laying a hand across the top of the machine, he stared off into space in pensive contemplation.

"Well?" she said at last. "Assessment?"

"What? Oh, yes, quite brilliant." He tapped one of the dense hoops encircling the drum. "Dwarfstar alloy. You were originally trying to dilate time with a localised gravity field, I take it?"

She shrugged. "Gravitic containment is proven technology for a wide range of nano-applications."

"But it's not an ideal environment for larger biological samples, is it?"

"Most organisms do not hold up well to having their extremities disarticulated, no. And there's the mass problem."

"So. You shifted to a novel approach. You're bleeding off energy not to freeze atoms in a near-motionless state—" he nodded towards the cryogenic tanks– "but to impede the natural flow of time, yes?"

"An oversimplification, but yes."

"Which is why Gallifrey interfered. You're dumping tachyon energy into the time vortex, right out of this universe. Entropy's frightfully efficient, you know. It doesn't need an assist."

"The net loss is virtually nil compared to the total energy of the universe."

"No doubt, but as soon as everyone starts clamouring for their own eternal veggie drawers, we'll be facing cosmic energy shortages." He raised his hands to forestall her next retort. "But I'm not here to quibble about that. No, I'm afraid your project is facing a more immediate problem. Two, in fact."

She folded her arms with a jaundiced look. "Here it comes."

"One, your device is bleeding off energy into the time vortex, but not quickly enough. I've been detecting tachyon micro-bursts leaking into ordinary space-time. Which brings us to the secondary problem."

"Side effects including nausea or headaches for time travelling busybodies?" she said.

"Well," he said, "you've essentially dammed time without providing a sufficient outlet. What you've built is not so much a stasis field generator as a time compressor. The spatial equivalent might be a diamond anvil squashing a planet down to the size of a gerbil. Sooner or later, something is bound to give."

"But that's impossible." She nodded towards the empty workstations. "Hathli has modelled the space-time stresses to sixteen dimensions."

"Ah, well, that's the trouble with transdimensional equations. Unless you set an arbitrary stopping point, they tend to go iterating off into infinity or tangling themselves up in a hopeless ball of string."

"What do you suggest?"

"I'm afraid I recommend abandoning this line of research. Triggering a temporal nova will be something to add to your name, posthumously, but the health risks to the people of this planet rather outweigh the benefits."

"Well, if that's how it has to be." She reached down and turned a dial on the top panel.

"Ah." The Doctor grimaced, pressing his thumb and forefinger against the corners of his eyes. "In the spirit of friendly scientific discourse, that's not exactly cricket."

"I'm going to have to ask you to leave my laboratory," she said. "If you'd like to discuss methods for refining the machine, my office hours are tomorrow, first period. I'd welcome some constructive input from an expert in the field. But I'm not about to let another ten years of work be erased because some self-proclaimed advanced civilisation wants to keep the invention of fire all to itself."

"Could you just—" he said, waving a hand feebly towards the machine.

"Out," she said. "Or I'll use _you_ to measure the tachyon leakage that you claim is eluding my instruments."

* * *

With a spreading grin, Tegan was listening to Lasarti as he waved his hands about, rapping the café table to punctuate his words.

"...And that was when it came to me: the mind is its own therapist! Dreams unlock the mental attic, letting us integrate the most recent day's experiences with our past. Dreams close it up again, too, putting away feelings and memories we don't need or aren't yet ready to face. But it's all so messy and random. So, what if we could create a lucid dreaming device that let us dream _and_ be conscious, have a say in the processes of integration, recall and occlusion? And what if a trained therapist could tag along as a guide—" Lasarti broke off, dimpling at Tegan. "Whoops, sorry. I'm getting carried away."

"Hey, don't apologise. It's fun watching you get airborne." Tegan took another sip of her coffee, surreptitiously inspecting this animated young man whom her best friend had married. With his dark olive complexion, gangly limbs, round cheeks and shoulder-length mop of black ringlets, he looked like a nerdy Greek wine god crossed with Mr Squiggle. Minus the pencil. "Anyway, what you're doing sounds fascinating. I've never even heard of psychometrics."

He pulled a face. "I'm not doing it, though, am I? Crane's got my prototype stashed away somewhere, and he's off on sabbatical. I can't even try to recreate it, not with his name on my proposal, sitting in the IPA queue waiting for peer review."

"You'll find a way. Sooner or later, the truth's bound to come out, right?"

That set off a rolling laugh. "You really aren't a scientist, are you? The annals of history are backfilled with footnotes: _Oh, by the way, the chap who invented the hyperspace transmitter? Didn't. His research assistant never got credit for it in her own lifetime._" Shrugging, he flicked a hand away. "But that's beside the point. The machine's not really mine nor Dr Crane's. It belongs to everybody it might help. There's people out there whose minds are fighting with them because of trauma, abuse, or just a way of being that doesn't mesh with the arbitrary patterns of our society. I want to help them help themselves. It may take me decades to make the oneirometer safe enough for routine therapy, and there's ethical issues to sort through. But right now, I can't even get started. It's maddening."

"Lasarti, you keep going around and around like that, and you'll drive yourself 'round the twist. Stick to what you can do for now, and keep your eyes peeled for doors in unexpected places. You'd be surprised what turns up." Like time machines masquerading as police boxes, which, come to think of it, had influenced his life as much as hers.

"But that's just what I'm doing," he said. "Professor Daskalos has offered to sponsor me. Without family connections–"

Tegan snorted. "That man? Please. He just wants to get his hands on your prototype."

"And now we're back to incompatible subjective realities." Lasarti gave her a wry grin. "Miss Jovanka, not to be rude, but why should I believe you? You're asking me to toss out everything I know about Professor Daskalos, and yet you can't tell me any details about what he's supposed to have done."

"What hasn'the done?" Tegan frowned. Where to start? Not Aunt Vanessa. That was too painful to talk about, and anyway, Lasarti's credulity was strained enough without her bringing up magical shrinking death rays. "I don't suppose you've ever heard of a place called Traken?"

"Traken. I... I think I've read the name in a history file somewhere, why?"

"Tell you a story. A fairy tale, except it all went balls up in the end. Once upon a time, there was a Planet of Insufferably Nice People. Gardens everywhere, advanced technology, no violence, no disease— paradise, if your idea of a good time was rewiring electronics or weeding. Until one day, your Daskalos wormed his way into their ruling council and seized control of the device that kept their world safe. Nowadays, you can't even find Traken on a star chart. An old friend of mine—" she chose her words with care— "was born there, and she saw it all happen. And the worst of it? All this business of getting inside people's heads? That's exactly what Daskalos did to her father. Wiped her dad clean away, poof, and took over his body."

Lasarti choked on his drink. "You're having me on," he said. He studied her strained expression. "You're _not_ having me on," he amended, dubious.

"Cross my heart. I've seen him use gadgets to control people's minds."_ And ones that can shrink you down to the size of that coffee cup,_ she thought grimly.

"But that's not possible." He nibbled absently on the rim of his cup. "Hypnosis doesn't work like that. You can't hypnotise someone who's actively resisting."

"Are you absolutely sure about that?" Tegan said. "What about this oneirometer of yours, letting shrinks go in and muck about in other people's heads?"

"That's not how it works." He looked uneasy. "And you still haven't given me anything but anecdotal evidence."

"Look, the only solid evidence you're to get is if he does it to you_._ By then it'll be too late!" Tegan voice rose in frustration.

He pursed his lips. "Well, there's a certain logic in that. But I'm still curious why you seem to care so much. You're not from Zarat; how could you even know about me?"

"I didn't. I saw Daskalos pulling his usual con job, and I had to get involved."

He shook his head. "Sorry, but I don't buy it. You _are_ stalking me. It's wigging me out a bit, although you're being terribly nice about it."

"Does it sound any better if I say that I don't give a damn about you, I just wanted to stick it to him?"

"The funny thing is, I don't believe that either. You really are worried about me. Who are you, Miss Jovanka, and who made you my guardian angel?"

"I told you. I'm just a space tourist, wandering the galaxy, seeing the sights, learning how people live on different planets." She gave him a bright smile, wishing the TARDIS came with cabin crew training seminars to teach one how to deal with unruly time paradoxes. "'Travel broadens the mind,' and all that. All I can tell you is this: you've got family you don't know you have, and one of 'em asked me to do you a good turn if I ever bumped into you. But I can't say who, so don't ask."

He threw up his hands in exasperation. "Now, honestly. You can't drop a thing like that on a chap without explaining."

"I'm sorry, Lasarti. Really, I wish I could. But I am telling you the truth."

"You believe what you say, at any rate." He leaned back, contemplating the multicoloured lanterns strung above the outdoor seating area. Finally, he pushed back his chair. "Well, this has all been rather... er, maybe not so illuminating, but certainly eye-opening. Now I think it's time I took your advice and stopped going in circles, which is exactly what this conversation is doing. Thanks awfully for an unusual afternoon. You've given me a lot to think about."

"Lasarti—"

"I said I'll think about it, all right? See you around." He winked as he stood. "Maybe I'll see you at Professor Daskalos' hypnosis seminar, first period tomorrow."

"Oh, that'll be a barrel of laughs." Tegan stood up to shake hands, but he was already gone, cutting a hasty retreat between tables and chairs like a skilled pilot navigating a reef. "Me and my blabbermouth. Why did I have to go and mention Traken?"

At a loss, she started to trail after him, just in case the Master was lurking around some dark corner waiting to spring. Thankfully, he was nowhere to be seen. Instead, Nyssa's head popped out from behind a nearby ivy-covered partition. She made eye contact, and then nipped out of sight again. Tegan cut across to join her in the secluded booth. "Whew! I was just beginning to wonder how long you wanted me on the job. Should I follow him?"

"No, no, it's all right. Thank you so much, Tegan." Some of the drawn lines in Nyssa's face eased.

"Hey, like I'd pass up a chance to snoop on the life you've been too shy to tell me about." Tegan bumped her shoulder with light knuckles. "So, what have you been up to besides tugging fire alarms? And what's this for?" She nodded at the sonic screwdriver-sized tool in Nyssa's hand. The bottom was uncapped, as if she had been tinkering with its innards before Tegan came over.

"Remember the instrument I used to build the Zero Cabinet?"

"What? No, sorry. If it's in the TARDIS and it's blinking, I leave it to you and the Doc." Tegan plopped onto the bench beside her, nudging her to scoot over. "Don't tell me, you're going to make another Zero Cabinet and stuff the Master inside. I'll just fetch a toilet plunger, shall I?"

Nyssa actually laughed. "I'm afraid not, although the idea has a certain appeal. An ion bonder is a tool for attaching and detaching molecular bonds. I discovered a long time ago that it can deliver a nasty shock, if miscalibrated."

"So?" Tegan's eyes narrowed, watching as she manipulated a row of tiny switches inside the instrument with the toothpick end of a drink umbrella. "Hang on. I thought I told you not to tackle the Master alone."

"I prefer not to, believe me." Turning away, she took surreptitious aim at the back of the booth. There was a faint green beam, a pop, and a jolt under them as if a sledgehammer had struck the stone. "There. Much better." She replaced the cover.

"Nyssa!" Tegan made a strangled sound of exasperation. "I swear you had more sense fifty years ago. Are you all right? What happened? I thought you looked a bit peaky."

"I gave him a piece of my mind. When he tried to help himself to the rest of it, I... left." Nyssa smiled wanly. "Tegan, I didn't go looking for him. He found me. And so..." She waggled the ion bonder, then tucked it away. "Now, tell me what happened after I left you. I was terribly worried."

"Aww, if you can handle him, so can I. It was kinda fun getting to be Danger Girl for a change." Briefly, Tegan recounted her run-in with the Master, the farce with Lasarti's pet, and her conversation with him afterwards in the café. "I hope I didn't screw up anything by telling Lasarti all that. He hasn't met you yet, right? I'm getting sick of time paradoxes."

"That makes two of us," Nyssa said. "Speaking of which, I had a minor disagreement with the Doctor. I didn't tell him about Lasarti, but he knows the Master's here. He was rather put out when I asked him to leave the matter to us."

"I don't blame him!" Tegan said. "We've got no business tangling with a Time Lord. The Doctor has enough trouble dealing with him, right?" There was a poignant silence. "Oh, Nyssa, don't give me those sad eyes. Spit it out."

"As you said: a time paradox. It's complicated."

"They always are. Look, I get that you can't tell the Doctor, but can't you tell me?"

"I think so." Nyssa laced her hands upon the table, fingers tightening as she spoke. "Do you remember my telling you about a farmhouse where I met the Doctor again, years after I left you? It was in a dream, a trap like Castrovalva, a psychic virtual environment created by the Master to ensnare the Doctor's mind during the very instant of his next regeneration. The dream suppressed the Doctor's memories of himself, providing him with an alternate, fictional life. But he was fighting it. His subconscious mind called out telepathically for help. The oneirometer allowed me to answer him and guide him back to himself. Lasarti helped, too. If we hadn't... well, I don't like to think what might have happened."

"No regeneration. And no more Doctor." Tegan reached out and stroked a thumb against the back of her wrist. "You had to watch him die again, didn't you?"

Nyssa looked away, voice constricting. "Yes. But it doesn't matter, as long as he regenerates."

"Into a stranger." Tegan sighed. "And you can't warn him, because it might set off a paradox if he knows his own future. Right?"

"Exactly. Furthermore, Lasarti and the Doctor can't meet now, because their first meeting is _then._ That timeline's so delicate, Tegan. If it changes in any way, I'm afraid we'll lose the Doctor. And possibly Lasarti and me as well, since we were trapped in the dream along with him."

"So that's why you've been so anxious. And you think the Master's trying to nab Lasarti and his gadget, to prevent you two from saving the Doctor's life?"

"It's the logical conclusion. But I refuse to allow him to interfere." Nyssa curled her hand over Tegan's, protective. "I hate to ask, Tegan, but since I also have to avoid Lasarti, I don't think I can manage this without you."

"Too right, you can't. Because I won't let you." Tegan spread her other hand across Nyssa's. "So what's the plan? Lasarti invited me to the Master's seminar on hypnosis first thing in the morning. Great scheduling, huh? All the students are probably half-asleep."

"And susceptible," Nyssa added soberly. She pondered. "That just might work. You can have another go at persuading Lasarti not to trust him, while I scour his office for evidence that might expose him as an impostor."

"Okay. Not much of a chance, but I suppose it's a place to start. Can't believe I'm volunteering to face that creep again."

Nyssa's face fell. "If you'd rather not—"

"No way! I'm going. It's not like he can pull too much funny business in front of a crowd. Now, what about that guided tour? I want to see where you're— where you will be living, I should say."

"Oh, Tegan, I'd love to, but I really think we should be getting back to the TARDIS. It would be just our luck to run into someone from my own future."

"You sure know how to show a girl a good time," Tegan grumbled. "All right, all right. Then can't we at least pick up some takeaway? If there's one thing I'm almost as sick of as time paradoxes, it's that food machine."

Nyssa smiled. "Come on. I'll cook us something."

"Oh, great. Petri dish cuisine."


	6. The Doctor's Medicine

Tegan burst out laughing when they reached the TARDIS. Someone had festooned the roof with garlands of paper flowers and planted a pair of colourful origami bouquets on either side of the door. Pine needles had been raked into a curving pathway leading to the doors with pebbles and broken shells providing a playful border. Chalk drawings of flowers and lizards decorated every empty panel of the TARDIS exterior. A placard dangled crookedly over the POLICE BOX sign, declaring in triumphant rainbow lettering: "ART HAPPENS."

"Oh, dear," Nyssa said, picking up a fallen flower and offering it to Tegan. "I don't think the Doctor has seen this."

"Hey, it's camouflage, right?" Tegan said, tucking it behind her ear. "Nobody's going to ask why there's a big blue box in the woods if it's got 'art department' scribbled all over it."

The door was unlocked. Inside, they found the deck strewn with tools, Turlough and the Doctor in shirtsleeves, and the Doctor with his head buried under the console. Turlough had the expression of a put-upon greyhound, although this was hardly unusual.

"Doctor," he said, "they're back."

"Mm? Oh, splendid. Pass me the turkey baster, will you?"

"The what?"

Tegan covered her mouth with her hands, stifling a laugh. "This is the genius we trust to put the TARDIS back in one piece?"

"I beg your pardon, I meant the Ganymede driver, of course," the Doctor said, his most dignified tones somewhat muffled by the console.

Nyssa selected a tool from the jumble of gadgetry spread across the floor and handed it to Turlough, who passed it down to the Doctor. "I'm cooking dinner tonight," she said. "For how many?"

"I'm going out," Turlough said. "In fact, I'm late. Tegan, take over for me."

"Me?" Tegan said, looking around at the mess in dismay. "But I don't know a whatsometer from a thingamajig!"

"Apparently, neither does he," said Turlough, scrambling to his feet and brushing off his trousers. Only he could manage to look furtive while snagging a tuxedo jacket from the hatstand and shrugging into it.

"A party?" Tegan said, eyeing Turlough's freshly washed hair, pressed trousers and neat silk tie, all a slight upgrade over his usual dour school uniform. "No, a date! Who's the girl?"

"Tegan," Nyssa chided. She caught Turlough's elbow as he reached for the door controls. "Just a moment." She reached up to give his suit's shoulders a tug and adjusted the poppy-coloured handkerchief in his lapel pocket. "There. You look very smart. Are you going to Glaston's?"

"However did you guess?"

"Your dinner companion fancies a man in a suit, so I infer upscale tastes. Avoid the amphibian entrées; there's an oil in the skin that's mildly toxic until the native microflora have enhanced your immune system."

He snorted. "Thanks, Mum. Now, if you'll excuse me." He bolted outside before anyone else could block his escape.

Tegan stared after him as Nyssa shut the doors. "Well, what do you know? He's not such a cold fish after all."

The Doctor's head popped out from under the console. His eyes darted from one woman to the other, studying them thoughtfully, although he affected a surprised smile. "Hello. Didn't hear you two come in. I trust you had a productive afternoon? Nyssa, give me a hand with this, will you? Turlough seems to have run off somewhere."

"Doctor." Nyssa stepped around some cabling and rapped the top of his head gently. "Dinner. I'll help you with repairs afterwards."

"I thought the auto-repairs were supposed to fix everything," Tegan said, eyeing the scattered bits and pieces with dismay.

"Presently, presently," the Doctor said. "But some of the auto-repair sensors were burned out as well. It won't hurt to give everything a once-over, just in case we need to take off in a hurry." He looked up at Nyssa.

She gave a subtle nod. "Best to be prepared."

His expression darkened. "Very well. I'll close up for now. What's on tonight's menu? If you need me to program the food machine—"

"Tegan's craving hand-cooked food. I'm indulging her. I might need your help in matching some of the ingredients."

"Oh," he said, sounding even more disgruntled. He had been tinkering with the food machine for centuries, and he took some pride in its eclectic cuisine from over three dozen worlds. Nyssa was content to sample his experiments, but Tegan, true to form, had a few things to say about the TARDIS menu.

"Hey, Nyssa, what's this?" Tegan said, picking up a pamphlet lying on the console. "'_Terminus Medical Station, putting health and care back into health care.' _Very snappy." She turned it over. "Cripes, you look ghastly. I hope you fired the photographer."

"I had a hospital to manage, Tegan. My looks were very far from a priority in those days." Nyssa glanced up, sensing the Doctor leaning over her shoulder. The disquiet on his face told her that he had not seen her picture until now.

"Did I ever mention how proud I was of your work on Terminus?" he said gruffly.

"Yes." She nudged him, tucking away a smile as Tegan began to make faces at her. "Come along, Doctor. The TARDIS surely won't mind if we leave her to air out until after supper."

* * *

"Barramundi Meunière," Tegan said, sniffing at the light sauce over the seafood dish that Nyssa had concocted. "I had something like this on the Cairns Esplanade once. I'm really not that big on fish and chips, but this is great!"

"Thanks," Nyssa said. "We're near the sea, so it's a little taste of home for me." She glanced at the morose-looking figure eating in silence at the other end of the table. "Doctor, are you all right?"

"More tachyon leakage," he muttered, staring over their heads. "I wonder how much longer that containment vessel's going to hold."

"Tachyons," Tegan said. "Rabbits, I'd forgotten all about that. Have you tracked down whatever's causing it?"

He shrugged and returned to picking at his food.

"Doctor," said Nyssa. "If that temporal disturbance is getting worse—"

"Well, that's my problem, isn't it?" He looked up, blinking owlishly at the two women staring at him. "Each of us has our own research project. How very traditional. Unless it's time for an interdepartmental collaboration? An exchange of information?"

Tegan turned to Nyssa, who gave a curt headshake. "I really don't think the two problems are related."

"You can't be sure of that!" Tegan said. "It's just like the Master to have his fingers in two pies at once."

"I know that," Nyssa said. "Besides, even if he's not involved, he's bound to notice eventually, if the Doctor's feeling the effects. Doctor, whathave you found?"

"Oh, just some humanoids messing around with dangers they don't fully understand." He tipped a hand towards the room at large. "There's a lot of it going about."

"Doctor," Nyssa said, coaxing. "We can't help if you don't tell us what's going on."

"How odd. That's just what I was thinking," he said, pushing back his chair. "I'm going to finish those repairs. The TARDIS won't object to my aid, at least."

Tegan jumped to her feet. "That's not fair, and you know it!" she snapped. "Nyssa's just trying to—"

"Tegan," Nyssa said in a low voice.

"Trying to what? Save my life?" He scowled. "By taking on the Master, while I twiddle about lecturing a university professor on lab safety. What an excellent use of our skills! Perhaps I'll let Turlough pilot the TARDIS, you can bowl for Stockbridge, and Nyssa can try her hand at air hostess. Yes, yes, I know, you're trying to avoid a temporal paradox. This _is_ a paradox, Tegan, or at least an oxymoron. Frankly, I can't see why Nyssa thinks her interference is any less likely to disrupt the timeline than mine."

"Look," Tegan said, voice rising to match his. "She's already had to fight one Time Lord today, so you just leave her alone!"

"And she wouldn't have had to fight him, if you two weren't so determined to follow Adric's spectacularly bad example of misplaced heroism!"

Nyssa caught Tegan's sleeve as she made to follow his stormy exit. "Please don't."

"He has no right to talk to you like that!" Her eyes welled up. "Nor me, neither!"

Nyssa drew her into a hug. "I know. It wasn't your idea. I'm the one who dragged you into this."

"That's not what I meant. You're just trying to look after the people you care about." Tegan's arms circled her. "And so am I. So am I."

Slumping, Nyssa rested her cheek against her friend's shoulder, listening to the Doctor's stomping footfalls fading away. "Give him time. How would you feel if I'd told you the Master was chasing me, then I ordered you away? Besides, the Doctor's never been the same since we lost Adric."

Tegan's bristling indignation slowly abated. "Yeah. I guess he cared after all."

"Of course he does. I doubt he'll ever forget, if he lives five thousand years. He just doesn't like to speak of the past. There's so much. It would crush him." She patted Tegan's shoulder. "Let me talk to him."

Tegan made a face. "What, now? Let him sulk. He's acting like a six-year-old."

"With which I have some experience," Nyssa said, "having raised two."

Tegan made a sceptical noise, but released her and shooed her away from the dishes. "Go on, go on. I'll clean up this lot. You know, Turlough was right. If I didn't know better, I'd think you and the Doctor were married. I can just see you two working the Sunday crossword together, arguing politics over dinner, sneaking out to the garage to tinker with old cars."

Nyssa shook her head. "But the Trakenite word for marriage means _match,_ not _inequality._"

Resting her mind on the soothing hum of the TARDIS, she had composed herself by the time she reached the console room. She was unsurprised to find the Doctor's long legs and striped trousers stretched out across the floor, obstructing the inner door. His head and shoulders were again hidden under the edge of the console. Stepping carefully over his legs, she sat down beside him and pulled her knees towards herself, waiting. He continued tinkering. There was a spark, a muffled oath, and silence. When he tossed a spanner aside and started to grope around on the floor next to him, Nyssa picked up a probe and set it in his hand. His fingers acknowledged hers with a brief touch before he dived back into the TARDIS circuits.

"I keep remembering," he said finally, "when you first called me back to Traken."

"Even before your regeneration, when you were... whatever the Watcher was." The melancholy warmth in her voice peeled away decades. "You terrified me. At first, I thought you were my father's ghost."

"You were barely more than a child. So innocent, so terribly vulnerable. I nearly left you behind."

"Yes. I'm very lucky you took the chance on me," she said, keeping her tone light. "Consul Katura said I was hallucinating, that I should ignore phantoms and visions, lest I fall to madness like my poor stepmother. But you promised to help me find my father, if he still lived. So I followed."

"Brave girl. I wish I had been able to keep that promise." There was an unpleasant scraping sound under the console. "Laser cutter?"

She was already dropping it into his hand. "But Doctor, you did. It was a shock, but I'm grateful that I could say goodbye to my father's face, even if he wasn't behind it any longer."

"As long as you travel with me, I'm afraid you'll keep running into him." There was another crackling spark and a scent of burnt polymer. "The Master's my responsibility, Nyssa. He shouldn't be yours."

She rummaged around for insulated pliers, slipping them into the open hatch beside his head. "Here. Doctor, I'm not going to argue with you. You simply must have faith in me and Tegan, as you've expected of us so many times. Is that so much to ask?"

"'Stay in the TARDIS. Wait here. Don't do anything rash.'" His grumbles boomed hollowly in the depths of the console. "A dose of the Doctor's own medicine, you mean?"

"If you like." Her lips twisted in a rueful smile. "Not so easy to swallow, is it?"

"I can't say I care for the taste, no."

"Nor I. It's been very comforting, stepping back into your shadow again. I'm going to miss that false sense of security."

"That's not entirely flattering. Have you been taking lessons from Tegan?"

"No. From you, remember?" She sat back, massaging her lower back with her knuckles. She wondered why such a long-lived race never worried about ergonomics. "You've stranded me in snowbanks, in besieged castles, in jails and brainwashing centres and spaceships open to hard vacuum. Sometimes I was angry at you for leaving me to fend for myself. But that training has served me well. Since I left, I've entered war zones, plague outbreaks, planets ravaged by biological warfare: places where a sheltered child of Traken would have been helpless. Nor have I always worked alone. I learned from you about the most difficult decision of all, when one is forced to let others shoulder the risk. I understand, Doctor, and I know how much harder that becomes, after you've lost someone under your authority."

He went still. She knew she was pushing him, but she also knew he was listening. So she pressed on.

"I can't promise you that Tegan and I shall be safe. But you can't either. All I can tell you is that you've prepared us. And thanks to your lessons on how to survive, I've been able to save thousands of lives." She let that sink in. "Thank you."

For a time, the hum of the TARDIS was the only language between them. Then: "Ratchet spanner?"

She took the pliers from his outstretched hand and swapped them as requested, feeling the firm squeeze that lingered against her palm.

* * *

"Are you gonna be up all night?" Tegan peeked around the door into Nyssa's bedroom, which she had converted into a small lab after moving back in with Tegan. The human grinned a little. Even as an older woman, Nyssa had a bad habit of analysing enzymes in her underwear. At least nowadays that consisted of white satin pyjamas. "Honestly, the least you can do is keep me company after I spent the day babysitting the boy you threw me over for."

Nyssa set down the slide she was preparing and swivelled her chair around, stunned. "What?"

"I'm joking!" Tegan said. "Come on. I don't want you bumping into Moriarty out there tomorrow on half a cup of coffee and no sleep."

"I... I need to finish this titration," Nyssa said, disconcerted. "Turlough's discovered a strange drug being distributed to the students. Give me twenty minutes. I can set up the analysis to run overnight."

"All right, Madame Curie." Tegan yawned. "Oh, don't look at me like that; I said I was teasing. I'm just glad you didn't turn out to be a nun, after all. Turn off the bathroom lights when you come in." Tegan's heels clicked away down the hallway.

Preoccupied as she was, it took rather longer than normal for Nyssa to program the spectrometer and secure the samples inside it. She was just tidying up her lab when there was a crash from the direction of the console room. Had the Doctor failed to close one of the access panels? The sound of a door slamming open and running footsteps put paid to that thought. She cast a dressing gown over her pyjamas, transferred the ion bonder to a pocket and stepped out into the corridor, nearly colliding with Turlough.

"Nyssa!" he hissed. "Nyssa, have you a medical kit? I need your help!"

"What's wrong?" she said, scanning his flushed face. "You didn't eat—"

"No, no, not me!" he said impatiently. "It's Vevik. I think he's having some sort of allergic reaction. He's passed out!"

"Keep it down, you two," Tegan groaned from the other side of the wall. "Whatever it is, can't it wait until morning?"

Nyssa felt her way along several roundels before tapping one and catching a first aid kit that popped out. "Show me," she said. "Where is he?"

"Console room." Turlough was wheezing. Nyssa guessed that he must have been carrying him. "Come on, Nyssa, hurry!"

She broke into a jog, keeping her voice low and soothing. "Were there any preliminary symptoms? Vomiting? Indigestion? Dizziness? Sweating?"

"Dizzy, shortness of breath, slurred speech. And his pulse has gone crazy."

They hurried into the console room, where the neat-looking young man whom Turlough had befriended earlier that day now lay on his back with Turlough's jacket rolled beneath his head. His brown skin was ashen grey, blotched purple at his cheeks, temples, and the backs of his hands.

"Did he mention any chronic illnesses?" Nyssa said, dropping to her knees and reaching for a wrist. It took three tries to locate his pulse.

"No," Turlough said, wringing his hands. "Nothing. He just started having trouble breathing. At first I thought it was only—" he blushed and trailed off. "He was _fine._ He seemed a little vague when we left the restaurant, but we were having a nice, quiet stroll though the grounds when he started to stumble over his words. Before I knew it, he was on the ground."

"That sounds very distressing." Lifting the young man's eyelids and peering at his pupils, she noticed broken capillaries around his irises. "It could be Dietz's Venacosis. But there's a maintenance drug for that, unless..." Distracted, she unbuttoned the young man's collar, fished out a patch from the medical kit, frowned at the expiration date, and applied it to the side of his throat over the carotid. "Did he try one of those new Stimsi formulations, do you think?"

"Yes, Vevik was the one who told me about the trials. Why, what have you found?"

"Nothing, yet. I couldn't detect any toxins or pathogens. I've programmed a molecular analysis that may tell us more. But the drug for Dietz is in the same family as the telomere stabiliser in hydromel."

"Hydromel?" Turlough stared down at his friend's face, barely attending. "That green slime?"

"Yes." She checked Vevik's pulse again: thready and irregular, but holding for now. "Never mind. The patch I administered should stave off vascular collapse, but we need to remove him to emergency care at once."

"But I don't know where that is!"

"Shh, it's all right. I'll call security dispatch. But I'm afraid I can't go with you. Some of the staff know me, or will do. Here." She fumbled in her dressing gown's pockets, pulling out her lab notebook and a pen to jot down instructions in medical shorthand.

Before she could finish, the Doctor appeared at the inner door, taking in the tableau at a glance and peering at the stranger laid out on the floor of his TARDIS. "Problem?"

"I think someone's been using our students for unsafe drug testing," Nyssa said. "Doctor, can you help carry him outside? I assume you'd prefer to avoid awkward questions."

"Indeed." The Doctor stooped. "Turlough, take his feet, would you?"

While they carried Vevik to a bench alongside the path skirting the woods, Nyssa hurried to the nearest directory, summoning a security cart for pickup. Vevik was stirring by the time she returned.

"Turlough?" he said, voice fuzzy and faint. "What is happening?"

"Easy there, friend," Turlough said, chafing his hands. "Help's on its way. It appears that the cheese _was_ poisoned."

"Cheese? I don't recall any... cheese?"

An electric cart's lights appeared in the distance, coming from the direction of the quad. "Here." Nyssa tore off the notes she had written, folded them neatly and pressed them into Turlough's hand with a pat. "Show this to EC's receptionist. That's a record of the patch I used, as well as my suspicions about drug interactions. Don't worry. They'll take good care of him."

"Thanks, but what do I—?"

She had already faded into the shadows of the trees, unsurprised to find the Doctor waiting for her. They walked back together, listening to the rise and fall of Turlough's agitated voice and the businesslike tones of the security guard. Stepping into the lee of the TARDIS, they hid from the cart's sweeping headlights until it glided out of sight. The Doctor let out an explosive sigh and pulled out his handkerchief, wiping at one of the chalk flower drawings.

"It'll all come off in the time vortex, won't it?" Nyssa said.

Stepping around to the front, he batted irritably at the dangling sign. "Probably."

"Poor Turlough," she added. "I think he's made a friend."

"Not another passenger, I trust. The TARDIS is already at capacity."

"Not once I've—" She stopped, looking towards the path they had just vacated. Was there a solitary figure standing under one of the lampposts beyond the trees? Raising her chin, she stepped resolutely into the bright light of the console room, turning her back on shadows.

The Doctor picked up something in her manner and hung back, pivoting on the threshold to peer into the darkness. But whether she had imagined it or not, the figure was gone. The Doctor operated the door controls with a scowl, shutting out the foggy night air. "I'll give you one more day. But if he's hunting you, Nyssa..."

By way of reply, she drew out the ion bonder and held it up, giving the base an emphatic twist.

"Why," he said, "that's mine, isn't it?"

"I've stepped up the ion rate. A nasty knock, even for a Time Lord." She slipped it back into her pocket and padded towards the inner door, a small figure in satin pyjamas and a dressing gown. "Goodnight, Doctor."

"I must remember, Tremas," he quoted to empty air, "never to fall out with your daughter." He had worn a different face the last time he uttered those words.

Then again, so had she.

And so had Tremas.


	7. Before the Storm

Three of the TARDIS residents were up and about by dawn, despite the previous evening's excitement. Tegan, on the other hand, was ready to smother Nyssa with a bolster when she came to rouse her somewhat later. "Oooh. After all that bumping around last night, the least you could do is let me sleep in." A tray with a steaming pot of tea, a plate of toast and a poached egg had appeared on a rattan footstool placed strategically in her line of sight. "And don't think bribery's going to work."

"Consider it an apology." Nyssa lifted the tea cozy and filled one of a pair of delicate teacups. "Lasarti's seminar begins in forty minutes."

"Fine. Why don't you go, then?" Tegan grumbled into the pillow. "He's your boyfriend."

Nyssa smiled, tightlipped. "I wish I could."

Groaning, Tegan sat up, lured by the scent of freshly poured tea. "Hang on. That's not the Doctor's snobby lee, is it? Where on Earth did you find Russian Caravan?"

"The café sells it. It's Taurian Tips, actually, but it's the closest I could manage—"

"To my favorite Brissie blend. With the royal treatment, yet." She recognised the pride of Nyssa's china collection, the Victoria &amp; Albert tea service, a bona-fide gift of Queen Victoria. Despite her Republican leanings, Tegan wished she had not missed that adventure. "All right, all right. You still owe me."

"I'll find the TARDIS hot tub?"

"Yeah, sure." At the best of times, it tended to wander, and nobody had seen it since the disastrous rendezvous with Terminus had caused several rooms to go missing. "And then we'll have to send a search party after you." Tegan dropped into the wicker peacock chair that Nyssa had pulled up for her and fell to.

Nyssa poured herself a cup, disguised the smoky aftertaste with milk, and sipped tea in companionable silence. Only when Tegan was finishing the last few bites did she venture, "You know to keep to crowded areas, right? Don't let him isolate you."

Tegan waved a hand and nodded, mouth full of egg.

"Good. Then, while you're at the seminar, I'll search the Master's office. But don't meet me there. That's where he tried to lure me, which means it's not safe. I'll find you at the café."

"No kidding." Tegan frowned and gulped the last mouthful. "So what's to stop him from catching you snooping around?"

"I'll be safely away before his seminar lets out, don't worry. It lasts one and a half periods, so I should have time."

"Ugh. I'm going to nod off before it's over."

"Drink your tea," Nyssa said, smiling. "You'll hardly be the first. But please, try to stay alert."

Tegan sobered. "Yeah. I'll try."

"Take this." She drew the ion bonder from the pocket of her coveralls and held it out. "I want you to have it, just in case. It should stun up to four metres. The beam is roughly the same shape as an electric torch's."

Tegan shook her head. "Oh, no. Absolutely not. You're the one going into the lion's den alone. You keep it."

"Tegan, please."

"I'd better get changed!" she said brightly, hopping up. "Fetch me one of my smocks, will you?"

Both were stubborn, but Tegan had the upper hand: she barricaded herself in the bathroom and refused to come out until Nyssa gave in. A short time later, Nyssa was bundling her out into a chilly, fog-drenched morning. Tegan was armed only with a campus map and the Terminus pamphlet, which she had rescued from the recycling bin. As Nyssa was squeezing her hand and wishing her luck, Turlough emerged out of the fog, damp and gloomy. To judge by his rumpled suit, he had slept in a chair. Tegan vanished into the mist with a wave as Nyssa drew Turlough inside.

"So, how is Vevik?" she said, steering him back into the kitchen for a warm breakfast.

"Sleeping," he said. "They've kept him on life support as a precaution. You might have told me how serious it was."

"There was no point in alarming you," she said, pouring him a cup of tea. "I couldn't be sure my diagnosis was correct. Besides, I knew they had the facilities to repair circulatory damage. It was Dietz's Syndrome, then?"

He nodded and sank into a chair. "So I gather. They were being awfully hush-hush about it. I wonder if that drug company bribed someone to do a cover-up."

"It's possible, but patient confidentiality is standard medical procedure. Speaking of Hydra Pharmaceuticals, your hunch was spot-on. There's something wrong with their new Stimsi formulation. Your unlucky friend's accident was a clue."

"Wrong? It's not really a poison, is it? I saw dozens of students trying it yesterday." He made a face. "I dumped mine into a cactus."

"By itself it's perfectly harmless, although mildly addictive. When combined with hydromel, however, or the drug that keeps Dietz's in check—"

"What exactly is hydromel?"

"A nutrient gel that shields chromosomes from radiation damage and boosts the immune system. It's absolutely vital for anyone stationed on Terminus. It's a powerful prophylactic against Lazar's Disease."

Turlough's brows knitted. "I take it this is some sort of medical sabotage?"

"Yes. The modified Stimsi binds with stomach enzymes to form a compound that weakens hydromel. The effect is more pronounced with Dietz's. With hydromel, it's so subtle that it would be difficult to detect. My staff would start coming down with Lazar's disease, and we wouldn't know why."

He frowned. "Why should anyone want to kill medical personnel? It's not as if you're dentists."

"Before it was shut down, the old Terminus Corporation used to be a subsidiary of Hydra Pharmaceuticals. Also, until I figured out how to synthesize hydromel in-house, Hydra was its only supplier."

Turlough gave a humourless chuckle. "And of course their hydromel wouldn't be affected by whatever they've done to Stimsi. So, at one stroke, they trigger an outbreak of disease among the staff, crush your hospital's credibility, and with any luck, kill _you_ off in revenge. Very neat."

"Turlough, I need you to do something for me after you've eaten." She hurried back to her room and returned with a padded envelope labelled in her precise, delicate capitals. "Here are the slides and readouts from my analysis. They should be sufficient to spark an investigation, assuming they fall into honest hands. Please deliver them to Dr Mikros, head of pathology. Tell him it's from me, Nyssa of Traken. No details, just that I was passing through and asked you to give it to him. Tell him it's confidential and urgent. Remind him that he mustn't contact me, since Hydra is sure to be monitoring all communications with Terminus."

"Can't you tell him yourself?"

She fluttered her fingers at her face. "This would require some explanation."

"Oh, right." He took the packet from her and laid it on the table next to his cup. "Do I get any thanks for this?"

"A great many." She smiled at him. "You've just saved the lives of most of my staff and many of our patients' families. Well done."

"You won't tell, will you? It will leave my reputation in shambles."

She nodded solemnly. "My lips are sealed."

* * *

Doctor Mikros, a broad grey lump of a man, was less than pleased by Turlough's surprise delivery. He demanded to know where "Lady Traken" was hiding and why she expected him to rattle Big Pharma's cage just when he was up for a large grant. He was a scientist, not a lawyer, and he had ten oral exams to administer in the next five weeks. Morosely concluding that somebody ought to do something about it, but that it was a damned shame an old man couldn't be left to his pathogens in peace, he took the packet but slammed the door in Turlough's face.

Privately sympathising with him, Turlough slipped off to explore another part of the building. Sure enough, he found the Doctor outside the cryogenics lab, pacing and fidgeting with a cricket ball.

"Morning," Turlough said.

"Hmm," said the Doctor. "Seen Nyssa about?"

Turlough shrugged. "In the TARDIS. She had me playing errand boy to one of her colleagues, helping her to discredit the company that's promised to pay me five thousand credits."

"That's the corporation using students as test subjects, yes? Incidentally, how is your friend?"

"You have a point," he admitted. "And he's on the mend, thanks. So, what are we doing here?"

"Waiting for one Professor Xertes, cryogenics expert, whose current project is building up to an explosion that could make all this—" he waved at their surroundings— "academic in a disturbingly metaphorical sense. By the way, is Tegan with Nyssa?"

Turlough shook his head. "No. Nyssa bustled her off on some other job. Do you have any idea what they're plotting?"

The Doctor smacked his palm with his knuckles in frustration. "Not the faintest. But whatever it is, that is notthe way to be going about it. They should stick together."

Turlough eyed him. "At the beginning of all this, Nyssa mentioned something about a dream analyst," he offered. "But I can't see what psychotherapy has to do with exploding tachyons."

"It doesn't. And whatever Nyssa told you, _I don't want to hear a word of it._"

Turlough retreated a step backwards with hands raised in appeasement. "Fine, fine. No need to chew my head off. I just thought you'd want to know."

"Well, that's just what we need," rasped an older woman's voice behind him. "Another Time Lord." Xertes swept up with her students in tow, barely sparing a glance at Turlough. "Well, Doctor? Have you come to badger, or assist?"

"Dr Xertes," the Doctor said, slipping the cricket ball back into his pocket. "Allow me to introduce my companion, Turlough. He's not from Gallifrey. I and my companions are travellers, as I said."

"That may be true," she said, unsealing the laboratory and stepping through a billowing curtain of vapour. "I downloaded some reports on your exploits..." She trailed off. The room was full of fog. A few light panels at their end of the room were flickering, but most of the enormous space was dark, lacking even emergency lighting. "No!" She set one hand on each of her assistants' shoulders. "Keep back, both of you."

"It wasn't like this last night," Hathli said. "Why didn't the alarms go off?"

The Doctor had already plunged into the fog. His voice drifted back to them. "Because your sensors ceased to operate many years ago. Professor Xertes, the pressure's building. You've had a nanosecond leak, and we're lucky your shielding absorbed the brunt of it. Otherwise, the people in this building would be dead of old age. In fact, new species might have evolved to replace them."

"Rubbish!" She raised her voice. "Hathli, Chrys, seize his assistant. Jonsmith, move away from the stasis field generator and tell me exactly what you did to it yesterday during your so-called inspection."

Turlough turned to bolt, but for once, his coward's reflexes failed to save him. Chrys' elbow caught him squarely in the groin. He squawked and collapsed in a writhing heap. "D-Doctor!" he groaned.

Hathli dropped to the floor across Turlough's chest and slipped an elbow under his ear, pinning him. "Now what, Professor?"

"There is no call for that!" said the Doctor. There was a faint chuffing noise and a shower of dusty and decayed insulation. Some of the ceiling fans sputtered to life, and the haze shrouding the room began to clear. The Doctor stepped away from the air conditioning controls and dusted himself off. "Now, perhaps we can see what we're doing."

"Professor," Chrys said, covering her nose with a cupped hand. "Look. The cryogenic tanks have defrosted."

"Ugh," Hathli said, curling a lip at the grisly black stains on the inside of the nearest glass tank. Most of them seemed to be inoperable, although there were a few near the entryway whose exteriors were still frosted. "This is going to be a hell of a biohaz cleanup."

"I'm waiting for an answer, Jonsmith," Xertes snapped.

"I've already told you, Professor. Your experiment is compressing space-time inside that chamber. Every second that ticks by adds to the strain. Sooner or later, something is going to rupture. Now, will you please release my friend? Fighting among ourselves is not going to solve temporal distortion."

Chrys had started towards the workstations and was passing her hands over the desk, trying to activate its holographic keyboard. The desk surface remained empty, and the glass display panels were dark. "Professor, the computers are down, too."

"As are most of your control mechanisms." The Doctor's voice was grim. "Professor Xertes, you can blame me, your grant committee, or the great god Dibbly Dobbly. Frankly, I don't care. All that's standing between us and a temporal rupture is your decayed synchrochron helix and a few dregs of power from Karpen batteries that could fail at any moment."

"But Karpen batteries last for a thousand years," Hathli objected.

"Excuse me," Turlough growled, still squirming under Halthi's bulk. "If I'm about to die of old age, I'd prefer to do it without some git sitting on top of me."

"Chrys, come away from there," Xertes said sharply. "All right, Hathli, release him. Chrys, I want you to contact Dean— Chrys!"

The girl had stooped to inspect one of the dead cryogen tanks. Suddenly she crumpled. At the same moment, the Doctor gasped and clapped a hand over his eyes. Recovering himself, he threw out his arms in warning. "Stay back!" He scooped up the girl and carried her towards the door. "Temporal burst. Several days, at least. Dehydration, malnutrition... she needs immediate medical treatment if you're to save her. Turlough, Hathli, move!"

"Right," Turlough said. "I wasn't keen on hanging around here anyway." He and Hathli took her from the Doctor and began to carry the limp, emaciated figure towards the lift. Meanwhile, Professor Xertes rushed to a directory panel in the hallway to summon an emergency medical pickup. When the doors had closed on the three young people, she sagged against the wall.

"I'm sorry," the Doctor said, bending over to catch his breath.

"Shut up." She composed herself and pulled up the building's public address system. "This is Professor Halcyon Xertes. I'm calling a Class QR evacuation of the BHR Centre. I repeat. Class QR. Lifts are permitted. You have ten minutes to exit the building. Do not shelter in place. Muster at secondary assembly points. Repeat, this is a Class QR evacuation."

Researchers began to trickle into the hallway, shooting nervous glances towards the cryogen lab as they hurried for the exits. Two of Xertes' colleagues slowed to cross-examine her, but she shooed them on, barking, "Move, move!"

"You should leave as well, Professor," the Doctor said. "My physiology is better-equipped to deal with localised time fluctuations."

"Until they stop being localised, in which case a distance of a few thousand kilometres will hardly matter."

"Well, yes." Without preamble, he turned and dashed towards the nearest elevator.

"Doctor, where are you going?"

"My TARDIS," he said, diving into the lift just ahead of the tide of people. "We'll need some equipment. Back before you know it!"

As she started to follow, a wheezing, groaning nose thundered inside the darkened cryogen lab. Xertes turned. "Shards, what now?" A blue rectangular shape was flickering in and out of view like a spent neon tube. "If that's your TARDIS, Jonsmith," she muttered, "it seems I'm not the only one with multiple systems failures."


	8. Snake Scars

Disorientated in the watery sunlight seeping through the morning fog, Tegan nearly missed the monolithic structure looming out of the mist. She joined the dribs and drabs of students streaming in through multiple doors. Planting herself at the top of the steep auditorium among the wheelchair spaces, she scanned the students filing past and searched the stadium seats below. Lasarti spotted her first. About two-thirds of the way down, he was standing and waving at her with both arms. With a surge of relief, she hurried down to him, scrambling over rows to slide into the empty seat he had saved.

"Morning! Wondered if you'd make it," he said, grinning. "Not much of a date, really."

"A date?" Her eyebrows climbed. "Uh, thanks? I wasn't sure whether you'd want to see me after yesterday."

Lasarti shrugged. "I'm a scientist. I can't resist a mystery. Besides, I flatter myself that maybe this is all much simpler than I'm making it out to be. Maybe you're just a discerning stranger who's fallen for my..."

"Roguish good looks?" She shook her head, amused. "Sorry to dash your hopes, Lasarti, but I'm just a friend of a friend."

He pouted. "I was going to say brains. No? Bugger. Ah, well, beauty is in the eye of the koniocortex."

Her chuckle faded as the Master strode out of the shadows of the back of the stage and raised his arms in a theatrical gesture, as if invoking unseen powers. "Good morning," he said, his commanding voice booming off the ceiling. Conversations died away with unnatural speed. Tegan looked around, disturbed to see just how many rapt faces were fixed on his. Hypnosis lessons, indeed. She began to feel uneasy. If he could dominate an entire lecture hall with his voice, a crowd was no refuge at all.

"Before we begin the praxis portion of today's lecture, are there any questions concerning last week's deep dive into the corpus callosum?" The Master surveyed the darkened auditorium, his gaze coming to rest squarely on her. Surely it was an illusion. He must be using some conjurer's trick meant to fool each person into thinking he was speaking directly to them. She glared out in defiance, just in case.

There were no questions. He let the silence percolate, then raised his arms again. "Very well. Today we will continue our experiment in memory recall. I trust you have all read the file on somatic imprints. Now. Settle yourselves comfortably. Breathe in. Breathe out. Breathe in... Cast your mind back... breathe out... back to the beginning of your chosen memory. You are there. You are perfectly safe. You are an observer of time, not its prisoner. Now, bring awareness to your hands. Manual memories are often deeply embedded. Look. Feel. Where are your hands? What are you doing with them?"

Tegan sat with arms folded as the lesson dragged on. From her perspective, the Master was conducting a classic hypnotist's stunt, leading his audience through a guided visualisation that, supposedly, retrieved forgotten details. The rise and fall of his showman's voice set her teeth on edge, not least because she was afraid he was implanting some kind of subliminal commands. For the moment, however, the exercise seemed harmless. He began to call upon volunteers to recount their memories.

Lasarti leaned close, whispering in Tegan's ear, "I've been thinking. Suppose I buy your story. Then what? I'm already on probation, thanks to Crane. If I walk away from Daskalos, he could have me expelled or revoke my fellowship."

"So? Get a job! Work your way up somewhere else. There's a whole universe out there, Lasarti. I've seen it."

"Oh, sure, if I want to abandon my work for mining or haulage. No one's going to hire an unlicensed psychology student without a degree."

"How about Terminus Medical Station? They're hiring. You'd better believe some of those patients could use a counsellor."

"Terminus!" He looked dismayed. "Wasn't it shuttered a few years ago? Some kind of malpractice scandal."

"It's under new management. Come on, it's not the cheeriest place in the world, but I know they'd give a bright guy like you a chance." Never mind how she knew. It felt strange recruiting for Terminus, after she had grown to hate its every last grill, rivet and air duct. Especially the air ducts.

"It sounds like you've been there."

She nodded. "Yeah. I know someone who caught Lazar's. The treatment saved her life."

"So it's true? I thought maybe the cure was all a corporate smokescreen."

"No. Look, I've got a pamphlet—"

"Miss Jovanka." The Master's smooth voice broke over them. "Perhaps you would care to share your memory with my students?"

She flinched. "You mean the one where some bearded maniac is chasing me around and around a beat-up cloister full of bad topiary? Not a chance." Titters broke out around the hall.

His smile widened. "Our current exercise concerns memory recall, Miss Jovanka, not _idée fixe._ I ask you please to focus upon the lesson and to cease distracting my pupils. Lasarti? In our last session, I believe you were recounting an accident at the stadium."

"Uh," Lasarti said, reddening. "Yeah. The stadium. Let's see…"

"Your hands, Lasarti. Please concentrate."

"Oh, right. My hands. I guess the main thing I remember is holding the bloke's hand. His right in my left. My fingers were sticky. I didn't notice the blood until my mate ragged me afterwards for not wearing gloves. I must've been pressing the ice against his forehead– the patient's, I mean, not my mate's— but I don't remember that bit. I guess my fingers were numb."

"I'm sure Miss Jovanka is duly impressed by your Good Samaritan credentials. We will now turn to dream retrieval, a more difficult endeavour which requires a deeper probing of the unconscious matrix..."

Lasarti covered his face with his hands as the instructor's attention shifted away. "It's not as exciting as it sounds," he muttered. "Just some poor drunk who tripped and cracked his head on the pavement. Security guards standing around doing bugger-all because they were afraid of lawsuits. I got a bag of ice from a beer vendor and stayed with him until the medics arrived. The stadium hotline refused to tell me what happened to him afterwards. I keep hoping I'll remember enough to track him down."

Tegan patted his arm. "I'm sure it was just a concussion. And you don't have to prove a thing to me. I'm supposed to be proving myself to you, remember?"

He grinned sidelong at her. "Oh. Right."

"Miss Jovanka," the Master said again. The laughter around the auditorium had taken on a different tone: more mocking, more cynical. She realised with a chill that it reminded her of the Master's oily chuckle.

She shot a quick glance at Lasarti to see that his attention was fixed upon her rather than the stage. "Yeah?"

"Since you've inserted yourself into my lecture hall, I assume you are willing to participate? Share a dream with us, perhaps?"

"A _dream?"_ she said. "No, thanks."

"A pity. There are fines and penalties for unregistered students attending a lecture. If you leave now, there will be no need for me to summon assistance."

The murmurs were growing hostile. She felt the audience as a wall of eyes behind her as she stood. "Or I could play along," she shot back. Lasarti gave her a quizzical look as she stepped over his knees and headed for the aisle leading down to the stage. "What's your game, then? You want to know what's on my mind? I'll be happy to oblige." She knew Nyssa would have six kinds of conniption, but a demo might be the quickest way to show Lasarti the Master's true colours.

The Master's eyes gleamed. With an old-fashioned bow, he beckoned her up onto the dais beside him. "Then the stage is yours, Miss Jovanka. Please, tell us what you are clearly unable to keep to yourself."

She set her hands on her hips. "Right. So, there's this snake oil salesman. He travels from planet to planet, conning the locals with one scam or another. I woke up before I could find out how he planned to exploit a bunch of psychology students in his latest harebrained scheme."

"Ah, Miss Jovanka, this is most illuminating: _idée fixe,_ ladies and gentlemen, as I noted earlier." The laughter ringing around the auditorium was definitely an uncanny echo of his own now. "Was there anyone with you in this dream? A friend, perhaps?"

Even on her guard, she felt a compulsion to answer. "N-no. No, I was alone."

"Come, come, Miss Jovanka. This is not the first occasion we have met, after all. I believe I am right in thinking that you have a companion named Nyss—"

"Manussa," Tegan said desperately, cutting him off before he said anything not meant for Lasarti's ears. "The dream took place on Manussa."

"Manussa, you say? Fascinating. Do continue." He curled his hand in midair, as if cupping her chin in a loose caress. "You are in the dream. Describe where you are, Tegan Jovanka."

Tegan was beginning to relax in spite of the eerie sensation of standing at the focal point of a huge parabolic mirror made of human eyes. "In a big classroom that's so squeaky clean there isn't even gum on the floor. If that's not suspicious, I don't know what is."

"Your dream," he prompted. "On Manussa. Manussa, the heart of the mighty Sumaran Empire. You were dreaming of a snake oil salesman... a snake charmer, perhaps? A snake." His teeth caressed the sibilants as if toying with them.

"A snake," she said. "Too right, a snake. He's... it's..." She tripped over the words, losing the thread of her thoughts.

"The snake. Follow it down. Follow. Follow the path of the snake. Where are you now?"

"In... in a cave. There's zigzags carved into the wall, like lightning bolts, like... rays. They all point to the same spot. A door, the jaws of a giant snake. You're there, you're a showman, barking out some flimflam routine... _step right up, step right up... see the fabulous Mara, forget your cares... _and there's people filing in, men and women and children, following the sound of your voice, lured up into the serpent's mouth... _my_ mouth... No! It's not me! It's you! You're the snake!"

"Are you sure, my dear?" the Master said gently. "Look down at your arm."

She shook her head like a shying horse. The queue of sacrificial victims was shuffling towards her, faces blank and expressionless. Aunt Vanessa was among them, escorted by a tall, grim man in black wearing a taller cylindrical hat. Behind them, the Monitor of Logopolis leaned heavily on Adric's shoulder, both of them chanting meaningless numbers. Nyssa swooped in from the wings, twirling in a low-cut gown of slashed black and crimson silks, dropping an elaborate curtsy. She rose en pointe to offer Tegan a chalice of wine. Her seductive smile was horrifyingly like the Master's.

Someone was shoving through the queue of docile victims, clattering up the steps to reach the dais where Tegan stood immobilised. "Sir!" It was a young man's voice. "Sir, she's unwell. End the demonstration. We need to take her to the infirmary."

A hand was cradling her forearm, massaging pressure points at the sides of her wrist. Or... returning the Mara to her? She recoiled at the touch.

"Lasarti," Daskalos said. "Compose yourself. As a therapist, you must be prepared for the unusual imagery that springs from the unconscious mind. It can be dangerous to rouse the patient prematurely."

Dim voices were hissing all around her now. The space had become a natural stone amphitheatre whose broken blocks were coated with dripping snakes. Myriad eyes pinned her with their gorgonian gaze. The cavern of the Mara had grown huge, its power amplified by the minds of many serpents twining and untwining, docile pawns of the snake charmer's will. Once more she was the Mara. They were the Mara. _He _was the Mara, surrounded by countless worshippers.

"But, sir!"

"You will obey me." The Master's voice had shed any pretence now, dropping to near-subharmonics as he issued commands for her ears alone. "Miss Jovanka, tell me what is on your wrist. Obey me. Obey."

Against her will, she found her eyes lowering. She gave a choked scream. The image was blurry, but there was an olive-brown snake tattoo coiling around her wrist like fingers…

She felt a sickening lurch, not from within, but from without. The pressure on her mind eased. The thing holding her wrist swayed, too. No, not a thing. It was Lasarti, looking as groggy as she felt. Beside them, the Master had grabbed onto the podium, teeth clenched in a spasm that quickly passed. A buzz of dissonant, uneasy whispers began to rustle around the vast chamber, like the first tentative birdsong after a storm.

The Master straightened with a grimace. "Ah, Doctor," he muttered. "Forever interfering, even when your lambs stray. Forgive me, my students, but I believe Lasarti is correct. Miss Jovanka needs to be escorted to the infirmary. You are dismissed!"

There was a chorus of gasps, as if from the throats of a hundred swimmers rising from a pool to draw breath. Bewildered and agitated voices broke out on all sides. There was nervous laughter, too: some students were taking refuge in nonchalant jokes.

"You two will follow me," the Master said. "Come with me."

Tegan fought against mental sludge. "I told you to shove off." She raised a fist, only to find the movement hindered by Lasarti's fingers curled loosely around her forearm. His face was slack. "And you're not taking him, either! Lasarti, wake up! Lasarti, snap out of it."

He stirred and raised his head, glassy-eyed. "What...? Professor, what's going on? What are you doing?"

The Master swayed again. He made an impatient gesture. "My office hours begin now, if you wish to continue this conversation." Turning, he strode stiff-backed to the door at the back of the stage and yanked it open.

Tegan clamped onto Lasarti's elbow as hard as she could to prevent him from following. His face reanimated as the Master vanished from view. "Ow. Could you please not break my arm? There's nerves in there, you know."

She breathed out and released her grip. "Ugh. Sorry. Now do you believe me? Do you remember what just happened? Did you see?"

"You... started to babble something about snakes. And then..." His brows knitted. "That wasn't even remotely ethical! Are you all right? Here, we need to get you to the infirmary."

"I'm fine," she insisted. "I'm more worried about you. Come on. I'm taking you back to your room."

"No," he said. His expression firmed. "No. I've got to talk to him. Someone needs to call him out. He's brilliant, you know, but he can't go around jabbing at people's complexes like that."

"So report him!" she said. "You saw what he just did. He could do anything to you!"

"Miss Jovanka." Lasarti was himself again, earnest and concerned. "Look, I can see why he upsets you. That demo was totally out of line. Even so, I've got to offer him a chance at rebuttal. It's not scientifically sound to pass judgment based on only one side of the story. So I'm going to confront him with everything you've told me."

"Lasarti, he just hypnotised an entire auditorium full of people,and you, and me, and I was resisting! You told me that wasn't possible. How much more proof do you need?"

His smile was sympathetic. "Get outside; get some fresh air. We'll talk after I've seen him." Before she could protest, he had turned and ducked into the sleepwalking crowd of dazed students.

"Lasarti, wait!"

"I'll meet you in the café!" he called. "One hour. See you then!"

"Lasarti!" After all her experiences in dodging alien tentacles and grasping androids, a press of human bodies should not have presented much difficulty. Nevertheless, by the time she had broken free of the crowd, there was no sign of him. With a sudden premonition of dread, she began accosting stragglers who shrank away from her. "Excuse me, I've forgotten where Professor Daskalos' office is... excuse me..."


	9. Breakdown

"Useless," Nyssa muttered, thumbing through a tray of old memory chips that surely predated the Master's arrival. Apart from student papers and lecture notes, there was no hint of the Master's presence in his spartan office. There were no pictures, no plants, not even a mug. She supposed she should be grateful there were no family photos. All she found was a notepad on which someone had been practising Crane's signature, and that was no proof of anything.

A light rain had begun to patter against the windows. She checked the chronometer above the door for the twentieth time. There had been a staggering moment earlier when the display's numbers had turned to gibberish and the whole world seemed to miss a beat, a sure sign that the Doctor's work was not going well. But time was his charge, and she had faith in his last-minute miracles. She had her own task to worry about.

There was only half a period left before the Master's seminar finished, and she needed to give herself time to clear the building. Sighing, she closed the desk and cast around for one last spot to search. Her gaze fell upon the tall, ugly, institutional metal bookcase that occupied most of one wall. She ought to inspect the rows of black, unlabelled binders that filled its shelves, but she was reluctant to touch them.

A sound froze her in the act of reaching for one.

Until she heard the click of boot-heels coming down the hallway, Nyssa had not known that she could recognise the Master's stride. It was almost but not quite the same as her father's. She wasted no time in bolting for the emergency hiding place she had scouted earlier. His voice sounded right outside the door, courteous but indistinct, answering a colleague's query. Turning sideways, Nyssa jammed herself into the gap between the bookcase and the window. Her reflection was dim on the rain-streaked glass, and there was no room for her to reach for the ion bonder.

The door swung open. She held her breath. Brisk footsteps crossed the carpet towards her hiding place. She could smell the very oil he used to sleek his hair.

Seconds crawled by. It was not like the Master to abstain from prey. She waited, waited longer, and finally steeled herself to step out into the room. She was not altogether surprised to find the office empty. She broke for the door, half expecting to crash into him as she fled. In her haste, she nearly upended two professors whose shocked reproaches followed her around the corner.

"Too close," she breathed, making for the exit. She was leaving empty-handed, but there was no help for it. Pulling up her hood, she stepped out into cold drizzle and hurried off towards the café to rendezvous with Tegan.

If she had stayed even a minute longer, she might have recognised another pattern of footsteps. Lasarti came marching down the hallway from the opposite direction. "Professor Daskalos," he called, reaching for the door handle. "Excuse me, sir, but I've got a bone to pick with you."

* * *

The TARDIS had finally yielded to the Doctor's coaxing and consented to land near the source of temporal distortion. Cables snaked from the console room, out through the open doors and into the manifold at the base of Xertes' machine. She and the Doctor were working in tandem now, bent forehead to forehead on opposite sides of the drum, eyes darting between their work and a tachyon meter that the Doctor had propped against the scaffolding. With delicate precision and coarse language, Xertes was attempting to replaced drained batteries with fresh power packs from the TARDIS stores. The Doctor, meanwhile, had his hands buried in the guts of the dying sychochron coils encircling the machine. He was trying to bleed off temporal energy, but he kept having to pause and recalibrate the stasis field to stave off a rupture. The professor winced every time there was an audible tap, click or spark from the Doctor's side of the machine.

Another automated announcement disturbed their concentration. _"Evacuation window is now closed. QR Evacuation Phase Three in one minute. Prepare to shelter in place." _

"Professor Xertes, I understand your reluctance to leave your invention in another's hands, but this really isn't necessary. My TARDIS can provide power until I've completed these adjustments. If you stay, and the containment field fails..." His face twisted in a sudden spasm. For a moment his hands stopped moving. The tachyon meter's graph shot up with wild oscillations that lasted for over a second before reverting to a slow, ominous climb.

_"QR Evacuation Phase Three in forty-five seconds. Prepare to shelter in place." _

"Not a chance," Xertes said. "Being able to sense stray tachyons won't do us a whole boiling lot of good if you become impaired. Besides, if my work's at fault, then it's my job to fix it. Conversely, if it's your sabotage, then I'll be damned if I leave you here to finish the job."

_"QR Evacuation in thirty seconds. Prepare to shelter in place."_

"Professor, if you have searched my history, then you must realise that Gallifrey didn't send me. I'm not here to hinder your work. In fact, I'm very impressed." He was also appalled, but there was no point in antagonising her by noting that he had not seen a time experiment this reckless since the Master had obliterated Atlantis by accident. "My sole concern is to prevent a disaster that could claim billions of lives."

_"QR Evacuation Phase Three in fifteen seconds."_

"Indicators point that way," she conceded. "They also point to the fact that disaster follows you wherever you land like a comet's tail flaring when it nears a star. Now stop yapping and get that synchochron recalibrated."

_"Five._"

_"Four."_

_"Three."_

"Professor—"

_"One."_

A rumbling thud, and another and another, shook the walls as if a slow rolling barrage was passing over and around them.

"That's done it," she said. "Dwarfstar alloy bulkheads. We're stuck in here for at least the next fourteen hours, unless hazmat teams give the all-clear."

"Dr. Xertes, the TARDIS shielding offers some protection, even with the doors open. Please. Leave this to me. There's no reason for you to risk exposure."

"You'll see reason enough if those power cables burp, and battery power's all that's staving off field collapse." Xertes scowled at the adapter she was cobbling together. Bootstrapping new batteries onto old with live current flowing through them was tricky enough, but the power packs from the TARDIS were made to an alien standard that required different plugs and a power converter. "Ha. No wonder you Gallifreyans need so many lives. People must throttle you on a regular basis."

"Not usually fatally. Why?"

"Twenty years I've been working on this project, and _now _a Time Lord's finally willing to let me see what makes your technology tick. Although I don't suppose you'd let me peek inside that time capsule's guts."

"I might do. Whether she would is another question."

"Oh?" Xertes snorted. "An exam-shy patient, eh? That must make maintenance a challenge."

"My TARDIS is perfectly capable of self-repair," he insisted, "but that tachyon surge we passed through gave her quite a beating. I fancy she's a little skittish of you and everything connected to your device."

"Which, at the moment," Xertes pointed out, "includes her."

"Yes, well." He patted one of the power cables. "I'll make it up to her later."

* * *

Normally the mild, soft rains of Nyssa's adopted home were relaxing, part of the daily rhythms of life outside the sterile walls of labs and time-ships. Today, Zarat's overcast skies, wet lawns and dripping trees seemed dreary. For Nyssa, this had been a lonely homecoming, arriving at the right place in the wrong year. Both Lasarti and her father were close by, yet cut off from her by a wall of time. At least she could get Lasarti back, but only by leaving her TARDIS family on the other side of that wall.

She dragged her thoughts back to the current problem. Her search had turned up nothing. The Master had burrowed his way under the skin of another unsuspecting community, and she had not yet found the leverage to dig him out. As long as he was here, Lasarti's life was in danger, whether or not Tegan managed to persuade him of the threat. Nyssa was still chewing on that tactical impasse when she heard splashing footsteps pelting up behind her. She swung around to see Tegan almost on top of her. Nyssa held out her hands, chiding herself for sending her friend out without a jacket.

"Nyssa!" Skidding on web cobbles, Tegan fell upon her gasping for breath. "Thank goodness. Nyssa, I've lost Lasarti!"

"What?" Heart quailing, Nyssa steered her away from passersby. It wasn't only the light drizzle streaking Tegan's eyeliner. "What happened? You're not hurt?"

"N-no! But... Lasarti. He went to confront Daskalos with what I'd told him. I tried to stop him, but—" Tegan hugged her in sheer frustration, words muffled against her shoulder. "Lasarti gave me the slip. Someone saw him go in, but he never came out. The room's empty!"

"Where?" Nyssa's hands tightened into fists behind Tegan's shoulders. "Not Daskalos' office! Oh, Tegan. I told you not to go there."

"What else could I do? Someone spotted you in the building. I was afraid you'd been trapped, too. Hey!" Tegan caught her sleeve as Nyssa pulled away. "Where are you going? They could be anywhere by now."

"Not necessarily. Did you hear a TARDIS?"

"Huh?"

"The sound of a TARDIS dematerialising."

"No, I didn't." Tegan straggled behind, wiping wet hair out of her eyes. "You mean that's where he's hiding it?"

"It's the logical place. In fact, I think I saw it."

"Nyssa, wait. You can't just barge in there. We've got to fetch the Doctor. Or," she said grudgingly, "at least Turlough."

"One more hostage won't help. And there's still a possibility that the Doctor will die, if we bring him into this." There was also a near-certainty that she could not help Lasarti without breaking the timeline or risking Tegan's life. Nyssa felt like she was juggling her heart in three pieces while the Master tried to snatch them out of the air.

"Hostage? No! No, Nyssa, you can't." Tegan hurried forward, planting herself in her friend's path. "I'm not letting you do that. You can't save him. You have to go to the Doctor. Time's going to be twisted up no matter what we do."

"Time." Nyssa stepped around her and kept walking. "Time itself is in danger. Didn't you feel it? The Doctor has bigger problems to worry about. I must protect my family."

"Nyssa!" Heads were beginning to turn as Tegan stopped making any effort to keep her voice down. "Do you really think the Master will release Lasarti in exchange for you? Why should he? Even if he did, you're an upgrade! Then all he has to do is wait for the Doctor to come after you!"

"I hope not." Nyssa felt in her pocket for the ion bonder. It was a most inadequate weapon. "And that's not what I intend. But if I fail, the fewer hostages, the better. You, too, Tegan. You've already had to endure enough for my sake."

"Uh-uh. You're stuck with me, unless you want everyone within earshot to know who you are. I don't need a fire alarm to attract attention, remember?"

"Tegan!"

"You can take your time paradox and shove it. Don't think I won't!"

"Very well," Nyssa said, catching her hand. "But hurry. You're right. The Master could leave at any time."

Tegan sighed and trotted faster. "You do have a plan, right?"

"Not really," Nyssa said, "but then, most of the time, neither does the Doctor."

* * *

Hathli was rapidly losing patience with a plodding receptionist who wanted a "plausible" one-sentence explanation for Chrys' condition. Turlough, equally fed up, crossed the packed waiting room and seized upon the nearest item that looked breakable. Lifting the glass workstation from the desk of an astonished clerk, he ripped it free and strode back towards the gurney.

"This girl needs priority care," he said. "Never mind what happened to her. She's suffering from acute dehydration and malnutrition. Hathli, wheel her into the next room. You lot, hook her up to full life support immediately, or so help me, I'm heaving this through the front doors."

In the astonished hubbub that followed, Hathli did as instructed, sweeping up a pair of bemused nurses along the way. Turlough lingered just long enough to see the IV go into the girl's shriveled arm. Then he deposited the monitor in a corner, exchanged a wry thumbs-up with Hathli, and ducked out through the curtains to make himself scarce. One of the orderlies from the morning shift had been staring at him, perhaps curious about the stranger who had brought in two different patients on the point of death in the space of twelve hours. Melting into the hallway, Turlough found his escape route blocked. The aggrieved clerk had cornered a pair of security guards inside the front entrance. Turlough thought her account of his misdemeanours was grossly exaggerated. He had not actually damaged the computer display, after all.

Retreating, Turlough withdrew into the warren of the main hospital block before they spotted him. He doubted his offenses were sufficient to warrant a room-to-room search. Even if they were, it would take some time for the sweep to reach the upper floors.

One person in the facility, at least, was glad to see him. "Turlough!" Vevik was propped up in bed, awake and smiling when he entered. "There you are! I was afraid you might depart before I had the opportunity of thanking you. I understand that you kept me company last night in a manner less gratifying than one could wish."

Turlough's ears coloured to clash with his hair. "It wasn't a problem," he said, folding himself into the window seat next to the bed. "So, how are you feeling?"

"Rather drained." Vevik's dark complexion was still blotchy and tinged with grey over cheekbones and forehead. He gave a wry chuckle. "All the more so after a lengthy conversation on vidlink with my father, persuading him not to sue Glaston's for food poisoning."

"Just as well you didn't. Glaston's wasn't to blame," Turlough said. "If your father's looking to sue, I'd save that Stimsi pack and pay a visit to Professor Mikros over in pathology. Once you're feeling better, I mean."

Vevik's brows arched. "This is not an idle suggestion, I take it."

"No." Turlough grimaced. "Vevik, a friendly word of advice: don't be so trusting. I asked a friend of mine to run an analysis on that free sample. According to her, the new formulation degrades the active ingredients in hydromel. She passed all the data to your university's head pathologist, who may have the authority to do something about it."

"Ah." Vevik sank back against the pillow. "Yes, that could well explain my symptoms."

"Right. So, how would your father feel about taking on a megacorp in the law courts?"

Vevik bared his teeth in a smile. "I think he will take it as a challenge. As shall I."

"A braver man than I." Turlough sighed. "And I can't help thinking my bad luck's rubbed off on you."

"On the contrary, Turlough, it is thanks to you that I am not dead. It seems I owe you another dinner."

Turlough's face fell. "Well..."

"...you are scheduled to leave Zarat shortly?" Vevik shrugged feebly. "Ah, well, you warned me as much. Your journey has been too eventful for such a peaceful world to hold much interest. In which case—" His voice abruptly rose to a squeak, then a buzz, then silence. All the lights on the monitors twinkled in a flicker almost too swift to see, while the instruments' bleeps sped up to an eerie trill. Jumping to his feet, Turlough was buffeted by a jarring twinge from head to toe. It felt as if not only his elbow but every nerve in his body had struck a sharp edge.

"Turlough, is something the matter?" Vevik said, as if the previous jangling three seconds had not occurred.

"Damn." Falling back into his seat, Turlough curled his fingers around empty air in helpless dismay. "Yes, and the Doctor will be right in the middle of it, as usual." He dropped his chin into his hands. It was tempting to ride out the storm right here, well away from the source of the temporal disturbance, especially after seeing what had happened to Chrys. On the other hand, if the tachyon leaks were growing so strong that even non-Gallifreyans could sense them, it might be prudent to seek shelter inside the TARDIS. He raised his head, eyeing the network of tubes and wires trapping Vevik in bed like a fly in a web. There was no hope of moving him, even if he were strong enough to walk.

Oblivious to Turlough's dilemma, Vevik smiled reassuringly. "Then you must waste no time in idle chatter. Go! Aid your captain of adventure. But do drop by, should you pass this way again."

Turlough hesitated, but he could do nothing more for his friend, at which point there was his own skin to consider. "I will. And..." He leaned forward to wring Vevik's hand. "I had a marvellous time. Despite my advice, it's great to be trusted for a change. You take care of yourself, my friend." He felt his ears reddening again as the heart monitor's quickening bleeps informed him of Vevik's response.

It was raining when Turlough emerged from the building. The long trudge back was interrupted by no more time-ripples, but that was small comfort. He felt like a sapper crossing a minefield. Or perhaps merely a sap. Why had Nyssa brought them here? And where was she, anyway, while the Doctor was busy trying to save her entire planet from extinction? Frustrated but resigned— it was hardly the first time he had been left in the dark, after all— Turlough slogged back to the grove, avoiding the clusters of evacuated scientists milling on the lawns. He resisted the urge to snare someone's umbrella.

Reaching the grove did not improve his mood. The TARDIS was gone. There was a square imprint in the needles where it had stood, framed by the swept pathway and sodden paper flowers, but even the "ART HAPPENS" placard had disappeared. Turlough groaned, making a desultory search of the ground in case the Doctor had left a note. Of course not. Which meant there was only one place the TARDIS could have gone: straight towards danger, as usual.

"Why does he always do that?" Turlough asked of the dismal cold drops falling on his scalp. "And why does everyone always have to go running off?"

By the time he returned to the paved roof of the BHR complex, the area was completely deserted, ominously so. The air was filled with a grating whine like a wasp's, presumably some kind of alarm. The digital display between the lifts was flashing * WARNING * QUARANTINE * RADIATION HAZARD * WARNING * QUARANTINE * RADIATION HAZARD *

"Wonderful," he muttered. He guessed that Dr Xertes had simply picked a standard protocol to clear the area as quickly as possible, but the dire warning was still unnerving.

When he reached the nearest lift, he noticed with consternation that the doors were open, but there was no car inside, just the cables and tracks of the exposed shaft. It was capped at ground level by a pair of metal bulkheads with only a narrow cutaway for the cables. As he stood gaping, another bulkhead rose silently from the ground at his feet, sealing off the front of the pod. The same thing happened as he turned to the next one, and the next.

"Everything under control, eh, Doctor?" he asked the air with biting sarcasm.

The TARDIS was down there somewhere, along with the only person who could fly it to safety through a temporal anomaly that might escalate to lethal levels at any moment. Turlough thought rebelliously that there were some justified grounds for murder, after all.

* * *

Nyssa listened at the office door. "Empty," she whispered before opening it.

Tegan followed her with trepidation, shutting the door behind her and bolting it. Nobody else needed to be caught up in this. Turning slowly, she scanned for any clue that she might have missed on her previous quick peek inside. Apart from the singular lack of clutter, there was nothing to suggest anything amiss. Nyssa headed to the hulking metal bookcase. She brushed one of the unmarked binders with a fingertip and jerked her hand away.

"That's it?" Tegan said, giving the bookcase a baleful look.

"I think so." Nyssa moved to the desk's workstation and disconnected its power lead. "Tegan." She gestured to her friend's feet and then towards the floor at the base of the camouflaged time capsule.

Tegan squinted, frowning as she deciphered the mimed hand signals. "Not much of a plan," she mouthed, bending to remove her mud-spattered shoes and set them where Nyssa indicated. The pointed heels jutted up like oversized caltrops.

"Tegan, we need to search the room," Nyssa said at normal volume. "Lasarti's prototype must be hidden around here somewhere."

Dread growing, Tegan began to circle the room, checking under the furniture, slamming drawers and opening cabinets. "What's it look like?"

"Most likely, an oblong box with a row of dials along the top and an array of electrode-tipped wires extending from a junction on its side." Ion bonder in hand, Nyssa was surreptitiously fusing the lead's ends to the wall on opposite sides of the bookcase at knee height. Tegan tried not to look in her direction, loudly rattling a case of memory chips as she lifted it and peered into the desk drawer.

"Please, my friends, dispense with the charade. It's not here, as you already know." They looked around wildly as the Master's hateful, disembodied chuckle filled the room. Nyssa flinched away from the bookcase just as he stepped out of it. The Master already had his Tissue Compression Eliminator trained on Tegan.

Heart in her mouth and the nightmare image of her aunt's shrunken body in her mind, Tegan threw herself to one side, plunging behind the desk. She missed the moment when his mocking smirk changed to a dead-fish gape as he stumbled over her discarded shoes and the tripwire. Darting in, Nyssa batted the tube-shaped weapon from his hand. Tegan rushed forward to help as the tiny woman fell upon him like a kitten pouncing a large dog, landing astride his back as he hit the carpet. He heaved under her, throwing her off-balance as she brought her cupped hands down to box his ears. Tegan made a dive for the TCE rolling across the floor. By the time she had come up with it, the Master had twisted, eel-like, and clamped onto Nyssa's forearms. She thrashed furiously, trying to dislodge his grip, but it was an uneven battle.

"Let go!" Tegan snapped. "Or I shrink that swelled head of yours!" Didn't Nyssa have a weapon, too? Tegan saw it on the floor by her knee and quickly shifted her gaze back to the Master.

"What, and kill us both?" The Master's sneer tempted Tegan to make good her threat. "Nyssa, my dear, I wonder that you still associate with such cretins." He grunted as she rammed her elbows hard against his chest.

Tegan circled the desk warily, tilting the weapon upwards. "All right, then, let's see what it does to your TARDIS."

The Master gave a derisive snort, but he wrestled Nyssa to her feet, all the same. He was using her as a shield.

Tegan shifted her aim above their heads, wishing she knew the weapon's cone of effect. "I'm warning you," she growled. "Nyssa's a tough lady. Get your grubby mitts off of her, or I shoot on a count of five... four... three..." She sought out her friend's eyes, frantically willing her to understand.

Nyssa was still twisting in the Master's grasp, but Tegan thought... hoped... she saw a nod.

"Miss Jovanka!" the Master snarled. "You will obey—"

"One," Tegan said, prayed, and depressed the button, aiming at the top third of the Master's TARDIS. Nyssa dropped like a snapped stage weight, catching the Master off-guard. Unfortunately, he was pulled down with her. There was a red ray, a flash, and a ricochet off some invisible barrier. Tegan ducked as one of the ceiling panels, now the size of a paper ticket, fluttered from its frame and dropped onto the desk in something of an anticlimax.

"Give that weapon to me," the Master said, wrenching one of Nyssa's arms behind her back. "You will give it to me. Give it to me, Miss Jovanka."

Tegan found herself stepping forward as the room began to recede.

"Tegan!" Nyssa said, sharp and fierce.

"Up yours, Prof!" Tegan said, snatching her hand back and glaring. "You murdered my Aunt Vanessa. Don't think I won't shoot!"

The alarm in his face dissolved into scorn. "I think not." Shoving Nyssa ahead of him, he took a half step towards Tegan. "Or you would already have done so. My dear Doctor, you send your young companions to keep your hands unsullied, but they haven't the will!" Eyes dancing with mockery, he closed his fingers around the TCE and reclaimed it with a triumphant grin. Tegan felt her stomach pouring through the soles of her feet as he reversed the weapon and pointed it at her. "So," he said, "Perhaps I should _eliminate_ these tiresome distractions, Nyssa?"

"I'm taking your TARDIS," Nyssa snapped.

Tegan's eyes widened as Nyssa wrenched free of his one-handed grip, stepped backwards, and vanished into the bookcase. The Master saw Tegan's horrified expression and whirled, charging after her.

"No!" Tegan cried. "Nyssa!"

As Tegan started to follow, a dreaded wheezing racket filled the air. She ran towards the ugly bookcase as it faded from view.

"Nyssa." She shuffled into the empty space like a sleepwalker, hands outstretched. Her palms found only blank, ordinary wall. She slumped against it, propping her forehead on her knuckles as the tears began to fall. "Oh, no. Nyssa, I'm all heart; you're supposed to be the brains! I never should've let you. We should've gone to the Doctor. Oh, Doctor."

Chilled, wet, and shaking, she collected her shoes and stumbled to the door.


	10. Dreams of Traken

"So, this is what you do for a living, hm?" Xertes said, face pressed dangerously close to live current as she inspected her jury-rigging for faults. "Hopping from planet to planet, sticking your nose in wherever it's not wanted, and mashing other people's noses in their messes?"

The Doctor was too intent on his work to give a proper response. Between the dizziness caused by the tachyon leakage and the challenge of trying to manipulate powerful forces with primitive equipment, he had misplaced his usual affability. Xertes was little more inclined to small talk. With a muttered oath, she sealed off the last junction and rerouted the current through the fresh batteries. Nothing exploded. Letting out a whistling sigh, she hopped down from her stepstool. "There. I think that should do it."

"It's incurable, you know, wanting to help," he said at last, bland face knitted with concentration. "You seem to have caught a touch of it yourself. As for me, I take a fancy to most worlds I visit, for one reason or another. Zarat, for example, won my hearts with its custom of using tea plants for hedges. An admirable practice; it would be a terrible shame to lose it."

"Well, that's true enough. But you don't fool me, Doctor. I'm sure my colleagues over in psychology would have a field day with your aliases." Glancing over at the tachyon meter, she grunted. "You're losing ground, Time Lord. Move over. I'll bleed off tachyon energy while you wrangle that containment field."

"Professor, please—"

There was another nauseating time-ripple. One of the couplings by the Doctor's knees let go with a loud pop as its breaker tripped. Xertes collapsed, catching herself on hands and knees.

"Dr Xertes!" The Doctor dropped the tool he was holding and crouched at her side. "Time's up, Professor. Into the TARDIS with you."

A buzzer sounded on the tachyon meter. Was it his imagination, or had Xertes' salt-and-pepper hair turned a shade whiter? She was still conscious, but the skin of her hands was shrivelled and dry. She was barely supporting her own weight. If she had taken a temporal burst of too many days without water, leaving her in the TARDIS might be a death sentence. "I beg your pardon, change of plans," he said, unceremoniously hoisting her and carrying her towards the exit. She was a rather stout woman, but luckily not very tall. "A few stray tachyons never hurt anyone," he said, "but temporal nanoleaks can ruin your whole day. You've earned a week off. Doctor's orders."

"Doctor... stop. _Idiot_. Containment field..." she coughed.

"Not to worry. It should hold for a short time without supervision. Which of these cryogen tubes is human-certified?"

Xertes did not answer. Her body sagged, arms loosening around his shoulders as she lost consciousness. Crossing to the far side of the room, the Doctor scanned the few tanks still in operation. There. One large tube in the corner stood empty. He felt time creaking under the pressure as he rushed to unseal the capsule, wrestle Xertes inside, and activate the suspended animation sequence that might preserve her until help arrived. Or it might kill her, in her weakened state. The sensor displays looked hopeful, at any rate. If he was interpreting them correctly, the bioscans showed readings on the low side of normal.

The tachyon meter's alarm recalled him to his task. Hurrying back, the Doctor found that the containment field had deteriorated during his absence. The odds stacked against him were piling ever higher. There was one mixed blessing. While two of the three power leads had tripped and broken their connections with the TARDIS, Xertes' new batteries were holding. Of course, they would last only so long as accelerated entropy did not gain the upper hand.

"Time to cheat, I think," he said, prying loose a panel that most certainly should not be opened. Xertes was no longer there to defend her machine against reckless improvisation.

He realised that he was going to have to start triggering nanoleaks on purpose to reduce the strain. The Doctor prayed that the heavy shielding between him and the surface would protect those aboveground. Zarat had indeed caught his fancy, as the home of someone dear to him. As always, he was keenly aware that there were three good friends among those he was fighting to save.

It would have given him little comfort to know that one of them was well out of blast range.

* * *

The Master advanced on the small figure bent over the console, palms mashed against the dematerialisation switch. Having no time to familiarise herself with the interface of a different TARDIS, Nyssa had simply pounced the first controls she recognised and flung the ship backwards in time. There was a vertiginous shudder as the Master's ship broke free of the tachyon field.

"That was unwise," he said, dragging her off the controls. "Most unwise. I now have everything I came for."

"Except the Doctor," she said, straightening with stiff dignity.

"Ah, yes." He gave a mocking bow and turned away, inputting new coordinates. "The Doctor. Well, I'm sure he'll be along shortly."

Nyssa wrapped her arms around herself and examined her surroundings. A silvery-grey heap near her feet gave her a start, but it was only an android— a mirroring-therapy android, in fact, probably Dr Crane's. Devoid of camouflage, it lay crumpled in a boneless sprawl with its head at an unnatural angle, staring up at her. She turned away. As her eyes adjusted to the dark but spacious room, she found herself gazing up at a nightmare from her distant past. She stifled a gasp.

Hidden in shadow, a web of metal struts and wires spanned one corner of the polygonal chamber from floor to ceiling, forming an irregular star-shaped polyhedron. Suspended in its midst was a spreadeagled figure, dressed in the coveralls and half-cape native to Zarat. Lasarti's tousled black hair covered half his face, and his mouth was slack and open. Fitful movement beneath his lids spoke of agitated dreams. Otherwise he was deathly still.

She had guessed he was here, but not how. It took every measure of willpower not to run into the web and try to pull him free. Yet she knew the Master was watching her for some outburst of emotion, and he would block any such attempt.

"Why?"she demanded.

"Really, my dear, I must thank you for drawing my attention to Lasarti's dream-research. Alas, I fear that the paper you co-wrote with your _partner—_" he twisted the verbal dagger— "demonstrated a deplorable lack of imagination. Such a waste. I shall unlock the device's true potential."

She watched, seething, as he sauntered past her and manoeuvred gracefully between the struts of the Hadron web. He went to a sleek black podium, to which had been bolted a makeshift control box whose basic design Nyssa had recently described to Tegan. Leads snaked from it into the larger apparatus, turning the web into a giant amplifier for Lasarti's prototype. The Master's gloved hands danced over the oneirometer's dials and switches as if taunting her. His victim's faint groan went to her heart.

"Open your eyes, boy. I am the Master, and you are my servant. Look down here. Look."

Lasarti's eyes flickered open, glazed and fearful as the command jerked him violently from delta sleep. He gazed down at them, uncomprehending.

"Release him," Nyssa said. "He's of absolutely no use to you. He's no prodigy." The last person she had seen trapped in that terrible web so many years ago was Adric, the Doctor's brilliant young companion, serving as the central processor for a sophisticated matter projection system.

"Do you think so little of your intended, my dear?" The Master adjusted a dial, and the young man gave a weak cry. "Lasarti, allow me to introduce you to my daughter, Nyssa. A time traveller like myself... and your future wife. In one future, at least."

Nyssa could practically feel the tides of time dragging the sand out from under her feet. Or, worse, tugging at her children. "Release him," she said again. "You don't need him."

"Quite correct. Thanks to you, his usefulness is at an end. Your psychic sensitivity will make the machine even more powerful. Strong enough to contact the Doctor's mind across time and space, once we have corrected the design flaws, perhaps?" He spread his hands, encompassing the complex interlocking struts of the web without quite touching them. "Planting unconscious suggestions, occluding memories, altering them or implanting new memories— your husband's preliminary research suggests a multitude of profitable avenues for study. And you, my dear Nyssa, will help me perfect them."

"No!" She saw Lasarti's pain-fogged eyes shift towards her. Bracing herself against the edge of the console, she tried to steady her voice, reaching out. "Lasarti, find a focus. Reach for one thing in your mind. Augmented hypnosis is still hypnosis. _Fight him_."

"Save your breath. He is subservient to my will, suspended halfway between sleeping and waking." The Master closed a switch and turned back to her. "Well, now. I see by your face that we are long overdue for a family reunion. Perhaps you would like to introduce me formally to this fine young man before we bid him adieu?"

She pressed her lips together, measuring the distance as the Master stalked towards her. Guessing the height of his kneecaps, she lashed out with her right foot. Before her boot could connect, a cold, unyielding fist closed around her left ankle and yanked. She fell badly. The back of her head struck the edge of the console on the way down. Stunned, she was barely aware of being lifted and carried by two pairs of arms, black and silver. As her consciousness faded, she heard a young man's voice in the back of her mind, indistinct and halting, muffled by grating static. He was humming the melody of a frivolous old show tune as sincerely as if it were a charm against demons.

* * *

Someone was stroking her hand. Her fingers felt too small, too smooth.

"She's coming around, my lord."

"Thank you, Sabian, that will be all." The raspy warmth in the older man's voice brought an answering leap from her heart. Nyssa opened her eyes at once.

She found herself lying on a mattress of woven rushes and ferns, cheek pressed against the smooth scrollwork of a briarwood bedframe. Deep-throated windchimes sang low and sweetly in the distance. Birdsong, a bubbling chorus of dagtails and crested avars, spoke of dawn not far off. She heard the shift and sway of heavy canvas, the flutter of leaves stirred by a gentle night breeze. Tree branches cast moon-shadows on the walls and pitched roof of the spacious, airy pavillion. Candlelight twinkled down through the cutwork glass of a great lantern wrapped around the tent's central pole like a lotus-shaped chandelier. All this she took in peripherally. Her gaze was enthralled by the white beard and kindly eyes of the man hovering over her.

"Father!" She tried to sit up, but her limbs refused to obey. There was a low throbbing ache at the back of her head. Her scalp tingled as if hairs were being tugged all over. "Oooh."

"Welcome back, Nyssa." Tenderly, he drew her into a sitting position. "Slowly. The fever has passed, but you are still very weak. The good Doctor returned you to us just in time."

"The Doctor?" she said, coming more fully awake. "Where is he?"

"The dreamer has gone," said a silvery voice. "Back to the stars and his time-ship. It was kind of him to look after you for so long."

Nyssa turned her head and recoiled against her father. A birdlike woman in dark robes with a waterfall of flax-coloured hair was beaming at her with the same tender smile as Tremas. There was an earthly warmth about her, and yet something was off. She seemed to be sitting in an isolated patch of moonlight. The glimmer of her skin, the highlights in her hair and the ring upon her finger were silver-white, not lantern-gold. It was this woman, Nyssa realized, who had been holding her hand as she slept. "Who... who are you?"

"Oh, my poor darling." Grey eyes like Nyssa's turned beseechingly to Tremas.

"Nyssa, Nyssa," he said. "Don't you recognise your own mother?"

"Mother!" Everything snapped into focus. The loving smiles of both her parents were almost too much to bear. Tremas lifted his daughter from the bed as lightly as a puppet, while the lady came forward to embrace them both. "Mother. I never thought to see you again." Nyssa felt curiously disembodied, stretched between joy and some other emotion she could not identify. The tingling beneath her scalp was becoming distressing, like an acupuncture session gone wrong. "What... what's happened? Where am I?"

"In our summer garden," the lady said. "Tremas thought the fresh air might revive you."

"On Traken," he said in a whisper that was a caress. "You're home, daughter. You're safe."

"Traken." Nyssa's eyes teared up, although she could not remember why.

An unobtrusive song, more sensed than heard, eased her heart. Their pageboy was no great minstrel, but the unsophisticated, alien melody made her smile. Resting her chin on her father's shoulder, she sought a glimpse of the dark boy bustling about the shadows of the pavilion, straightening cushions and sweeping out the leaves that had drifted in across the carpet. The youth's drawn face was half hidden by black hair falling in straggling ringlets over his eyes.

Her discomfort was becoming more difficult to ignore. It felt like a swarm of burrowing insects tunnelling between her brain and her cranium. She bit back a whimper, trying not to alarm her parents. The boy looked up, brow furrowed, and retuned to his duties.

When she opened her eyes again, bright daylight was colouring the pavilion walls and roof a pinkish gold, laced by blue tree-shadows. The drowsy afternoon susurrus of birds and insects had replaced the boy's intermittent humming. She sat at the mosaic-topped round table that she and her father had built when she was younger, its crazed top an uneven surface for wooden panniers of fruits and cheeses and home-baked bread. Her mother swooped over her shoulder to set a steaming cup before her. Nyssa raised it in both hands and inhaled deeply to breathe in the steam, basking in the delicious aroma of blended herbs that reminded her powerfully of home.

Her father's laughing eyes met hers from across the table. "Cricket?" he said. "A curious name. Is it a game played with insects?"

"N-no," she said, dragging her attention back to the conversation. "With a red ball and a wooden bat. The Doctor has a closet full of them and those silly jumpers he wears. They're part of his uniform."

"And where does he play this... cricket? In his TARDIS?"

"No, on Earth. It's his favourite planet."

"Earth." Tremas leaned forward, steepling his hands on the table. "Where, exactly, on Earth?"

"Well..." She frowned, distracted. She had lost sight of the pageboy, which troubled her. She could no longer hear his singing in the background.

Mother, standing beside her, placed her hands on the girl's shoulders. "Your father and I are eager to hear of your travels, Nyssa, and of this Doctor who fostered you so well."

"Indeed. Tell us, Nyssa, was there any place on Earth that held special significance for the Doctor? A home, of sorts?" Father's hypnotic voiced lulled her into a dreamy reverie, distracting her from the sparking jabs of pain that were digging into her scalp like a barbed net.

His query prompted a memory, a poem that the Doctor had recited from time to time. _Sweet smiling village, loveliest of the lawn..._ "Stockbridge," she said. "An English village. There were thatched houses and an inn and a post office around the village green. That's where they erected the spring May Pole and played cricket in summer and autumn."

"Oh, that sounds delightful," Mother said. "I can almost picture it, when your eyes shine so." In fact, it seemed to Nyssa that she could hear the crack of the bat and cheers of _Six! _from unseen spectators. The smell of fresh-cut grass wafted into the pavillion. Then scent and sound withdrew, leaving her with a vague sense of melancholy, like spoiled endings. _Thy sports are fled, and all thy charms withdrawn..._

"These houses," Father pressed. "What were they like?"

"Old farmhouses, for the most part. Plank floors, wooden beams and white plaster walls, with a roof of heavy thatch that was blooming by midsummer. Only a few rooms, but a ground floor and a loft." The pavilion itself seemed to mimic her words. The walls were whiter now, the corner-posts darker, and the carpet had changed to floorboards.

"What quaint, primitive architecture," said Mother.

Father gave a strange smile. "So, the Doctor fritters away his time in a human village for entire seasons. How careless of him. And what does he do there when winter comes?"

"Winter?" Nyssa flinched. The pain was making it hard to think, banishing smoky memories of a farmhouse's front parlour with its roaring fire and two stuffed armchairs and a tea service set for one. _Amidst thy bowers the tyrant's hand is seen..._

"Shhh, my darling," said mother, settling on the trestle-bench beside her and taking her hand. "Does it hurt to remember?"

"N-no... yes, but no. Winter is when he... when he rests. The snow piles up outside, all around the farmhouse and the barn and the trees in the forest beyond..." She remembered black bare trunks against the stark white, the weight of the Doctor leaning heavily on her, a weight like unshed tears, the crunch of their footsteps in the barren snow... _And desolation saddens all thy green..._

The boy's far-off humming came to her again, distorted by a crackle like feedback. His playful jingle seemed to poke fun at the Doctor's pompous, sober poetry. And yet, in a curious way, the poem and the song were akin. Both seemed more real, more true than her parents' voices. Why were Mother and Father so eager to learn of the Doctor's bolthole in Stockbridge? Why was she speaking so freely of it now, when she had never even told Tegan of that secret haven? Tegan. Where was she, in all this? Had Tegan accompanied the Doctor when he brought Nyssa home to Traken? Had they said goodbye properly this time? Had she met Mother? How could Mother even be here, when— when—

Seized by an abrupt, violent impulse, Nyssa dug her fingernails into the woman's palm. The lady's tranquil expression did not alter in the slightest, although the attack should have drawn blood. "Mother is dead," the girl said, angry and desolate. "And how can the Doctor have brought me here, when I saw Traken—"

"Nyssa, Nyssa," Tremas said, rising to his feet. Her head was throbbing now, as if the insects had turned into jagged filings of heated metal. "Forgive us, child. We've confused you with too many questions. You need more rest." Her mother had pulled up a reclining chair. Father lifted her from the trestle-bench and settled her into it. Taking a blanket from his wife's hands, he bent to tuck it in, wrapping the edges snugly around Nyssa and the arms of the chair.

"No!"Nyssa kicked and fought, suddenly repulsed by the silvery woman's inhuman smile and her father's broad, toothy grin. _Only one master grasps the whole domain..._

Smiles. She had loved her father's smile once. No longer.

"You are not Father," she said, enunciating each word with bleak, quiet clarity. The agony was growing unbearable, but she fixed him with a level stare. "Nor are you master of anything: not Traken, not Earth, not the Doctor, and certainly not me. Traken is mine; it was never yours. Get _out!"_

Her childhood playhouse tore itself apart with a loud crack of tearing canvas. It felt like her own skull had been ripped in two. She came up gasping, thrashing, pushing against the hands that held her. A snarl at her ear made her freeze.

"Be still, _my lady_." He laced the title with ironic, mocking courtesy. "Hadron power lines are lethal to the touch." She realised that her out-thrust hand was a finger's breadth from a strut carrying live current. Its charge was lifting the hairs on her skin. She went limp, letting her arm drop. With a dismissive snort, the Master raised his eyes to address someone standing behind her. "Could you make any sense out of all that pretty prattle, Kamelion?"

"Yes, Master," came the metallic reply. "I was able to collect several key images that may prove suitable. More data will enhance the simulation."

"Excellent," the Master said. "Shortcuts, weak points, _sentiment: _bait to lure the Doctor into a prison fashioned of his own infantile fantasies. We'll need his own memories to flesh out the cage, but it's proof of concept. A useful start. And her mind is better able to withstand the feedback than the boy's. I think we may now dispense with young Lasarti's services."

Nyssa stirred weakly against the rigid chair to which she was bound by one arm. Her scalp still prickled where the electrodes had torn loose. Lasarti hung above her, his face in shadow, breathing uneven. Her mind was too clouded to calculate odds, but she knew her half-formed plan was desperate, possibly suicidal. Nor had she any idea what a short circuit might do to Lasarti. But this was her last chance to act. Pushing off against the Master, she threw herself backwards, crashing into Kamelion's shins.

The android teetered. There was a metallic shriek as it touched the power lines. Nyssa's whole body jerked from the secondhand jolt, but she landed on the floor, not against the web or the unfortunate robot. The Master gave an incoherent bark of rage and turned away, twisting dials on the oneirometer to reduce the power. Above him, Lasarti took a convulsive breath, straining feebly against his bonds. He was awake. She thought she saw his lips moving in a silent mantra. He must be using one of his grandmother's songs as a focus. An image came to her: Lasarti's lanky frame bent over a crib, soothing the sobs of a colicky baby with that kindly voice that made him such a good therapist.

"Kamelion, step away from there!" the Master said. "Damage report!"

The inhuman voice buzzed like a dying speaker. "Status... status... status... Error. Reset initiaaaaaaaatteeeeeeedddddddd—" It trailed off in a rattle of static and continued to whine like a jammed intercom.

"Return to the lab," the Master snapped, jabbing a finger towards the inner door of his TARDIS. "Full shut down. I shall deal with you later."

Still buzzing, the android obeyed, exiting the room on unsteady legs.

"As for you_,_" the Master said, stooping to set a gloved hand around Nyssa's throat, dragging her and the chair upright, "That was foolish." He returned his attention to the strap around her wrist, giving it a savage yank. "Tell me, Nyssa of Traken, how exactly do you wish me to dispose of your beloved's body?"


	11. Unremember Me

Probabilities collapsed into mere seconds as Nyssa searched desperately for a way out, remembering the Doctor's credo that the slimmest chance could be turned to one's advantage. She snatched her unbound arm away as the Master reached for her wrist to secure it. Glancing up, she found Lasarti's frightened eyes locked onto hers. She could see the stuttering rise and fall of his chest, near panic mirroring her own. Almost she wished he were still swaddled in dreams, unaware of the guillotine. And yet—

Dreams. A way.

Squirming like an unruly patient to keep one hand free, she gave Lasarti a firm smile. _Help,_ she mouthed. Her gaze flicked to the black-clad figure stooping over her. _Distract._

"Enough," the Master said, pressing a thumb against the side of her throat. Her field of vision began to shrink. "I can simply render you unconscious, if you intend to be diffic— ah!" His grip loosened. "Lasarti! Stop that at once!"

Nyssa felt it, too, an excruciating sensation like a pole-axe driven straight into her vitals. Her medical training identified it as a kidney stone, or the memory of one. The rest of her wanted to curl into a helpless, writhing ball, dig out the foreign body with a blunt spoon. Instead, she punched the heel of her hand hard against the Master's chin. His teeth clacked together as his head snapped up and back. He was already recovering as she reached across her body to the pocket he had been too arrogant to search. Green light flared. She saw the beam reflected in his furious eyes just before he stiffened, face frozen in a sneer, and fell across her legs.

Heart pounding, she crawled out from under his deadweight and unlatched the strap cutting into her wrist. The stabbing pain began to ease. She rose just in time to catch Lasarti's chin in her hands as his head lolled forward.

His voice was barely audible. "Can I stop concentrating now?"

Nyssa checked the urge to stand on tiptoe and kiss him. "Yes. End of session."

Silence. The Master's TARDIS was sterile and quiet, no soothing hum to break the stillness, only Lasarti's ragged panting. Nyssa allowed herself a moment to simply _be,_ catching her breath. She gazed up and back across the years to an unlined face she had fallen in love with almost forty years ago, wiped clean of all their shared history. She could feel his pulse pounding under her thumbs, the clammy sheen of sweat on his cold skin.

Her fault. The Master must have learned of his existence while hunting for her. Now she knew how the Doctor must feel every time a companion was threatened for his sake.

Lasarti blinked down at her. "Why, hello." A shiver passed through him. "Ow. Needs refinement before it's ready for human trials. Could I trouble you to unhook me?"

"Hold on." She patted his cheek. "I'd better power down first. I think you've had enough shocks for one day." The Master warranted a suspicious glance— two— before she turned her attention to the oneirometer. Shadows obscured the settings, but what she could see was enough to set her teeth on edge. Gently, she adjusted the dials to safer frequencies. "There. Is that better?"

"Yes." His eyes widened. "Yes! What did you do? The feedback's gone!"

"You'll work it out," she said with a tight smile. "You don't want to know what he'd set it to."

He groaned. "The man's a sadist."

"I'm afraid so." With pitiless pragmatism, she stunned their would-be captor again. "Can you bear to wait a little longer? I've got to secure him. I don't want him waking while my back is turned."

Lasarti shrank from the bright light. "Uh... sure. I'm not going anywhere." Cowed, he added, "You didn't kill him?"

"No!" The question gave her pause. She recalled a chilling conversation with an assassin whose courteous but callous amorality had reminded her of the man now lying at her feet.

_"He's out there, a creature with my father's face causing what pain he can to others. Do you know how much that hurts?"_

_"No. Honestly, my lady, I do not. But I do know how much better you would feel if that creature were dead. You must have vengeance."_

_"How could I destroy the one thing I have left of my father?"_

_"That is only a façade. You must kill him. That is the only way to let him go."_

Vengeance was pointless. But what of the deaths piled up like autumn leaves wherever the Master travelled? She could end his predations here and now, spare others the same fate as her father and her world.

And become an assassin. That was the boundary she had never seen the Doctor cross: he would fight in self-defence or to prevent murder in the moment, but never based on foreknowledge of evils yet to come.

"No," she said, eyes darkening. "Try to rest. I'll be as quick as I can." She closed the Master's eyelids with a gentle touch for the man he no longer was, hooked her arms under his shoulders and began to haul him towards the inner door of the control room. "It was very well done, Lasarti. Thank you."

"Huh? Oh... the dream. Sorry. You felt that, didn't you?"

She laughed a little. "It's all right. I'm a mother. I have some experience with pain management."

"I'll say. Personally, I was howling like a—" he broke off. "Hey! 'Family I don't know I have.' That was you she meant, wasn't it?"

"Yes. Tegan is my best friend. I'm glad you've finally met her." Giving the Master's body a rough heave, she rolled him into the hallway and closed the door. Then it was time for the ion bonder to be set to its proper use.

"Please tell her thanks and... sorry I didn't listen." His bleary eyes followed her every movement like a child watching an exotic insect with mingled wonder and fear. "Nyssa. He called you Nyssa. We're to be married?"

Her heart sank. So, Lasarti had been conscious enough to overhear. The timeline had altered, despite her best efforts. Giving the ion bonder an angry twist, she set to work fusing the door to its frame. She suppressed a barbaric impulse to bond the Master's skin and clothes to the floor. He was not worthy of her attention, unlike the young man behind her.

Pausing to look over her shoulder, she flashed a reassuring smile. "How do you do, Lasarti?"

"Rather poorly just now, to be honest, but at least the company has improved." A ghost of his impish grin flickered, tentative. "Er... aren't I a tad young for you?"

"Indeed. You will be very young at heart when we meet. And I was younger and prettier, if that matters."

"Not in the slightest, ma'am." She could hear the blush in his voice.

"I'm also housebroken, and I can even count to ten. But seriously, lads have a whole vocabulary for professors who look like you." He was beginning to relax, despite his nervous chuckle. "You're a scientist?"

"Naturally. You'll need someone who can follow your nattering, when you start to dribble on about psychometrics and lossless synthetic synaptic gaps."

He gave a delighted woof of laughter. "From nightmare to dream come true in an hour? Pinch me. No, scratch that, things are moving way, way too fast for me already."

She sat back on her heels, giving the molecular bonds a moment to cool. "About that," she said. "This isn't how we're supposed to meet, Lasarti. I was coming home many years from now, but an accident threw my ship back in time. I never meant for you to meet me— not now, not like this. But it amused Daskalos to tamper with the sequence of our lives."

"I don't much like your father."

"He's not really my father." Bracing herself, she lunged against the door with all the force she could muster. A few more bruises were worth the assurance that it was now, simply, a wall. "The Master, he likes to call himself. He's hurt me before, and now he's robbed you of chances, choices." Massaging her shoulder, she hurried back into the deadly web, chafing at yet another half-victory that nothing could amend. The bump at the back of her head was beginning to throb.

"You mean, I have to marry you, because I know I will?"

"Exactly." She looked up, hands knotted at her sides as she studied the restraints and wires ensnaring him. "Lasarti, I don't want our life together to be predicated on nothing more than the arbitrary dictates of a time-loop. Your spontaneity was one of your greatest gifts to me. How dare he rob us of that!"

"It does rather take away the fun of getting to know one another, doesn't it?" His mercurial grin drained away. "You know how to operate this thing, don't you?"

"Yes, but it's only the prototype." Resigned, she reached up to unstick one of the leads fanned across his temples. "I'm tempted to undo what he's done. But it's too dangerous. I might damage you."

Lasarti shook his head, blocking her from peeling the electrode away. "Do it. Otherwise we'll always have this hanging over us. And couples therapy isn't cheap."

"What if I occluded the wrong memories?"

He drew a shaky breath. "I trust you."

His naive faith touched her. Yet she dared not forget the threat of the Master stretched out on the floor with only one door between them. He might wake at any moment. But at the thought of him, her stubbornness flared. He would not steal their future. With a decisive nod, she reached for Lasarti's arms, feeling for the catches to release him. "If you're sure. But let's get you down, first. I can't bear seeing you up there."

She needed his help to extricate him, in any case. Precious minutes ticked by while she slipped his bonds, resting his forearms against her shoulders. He radiated a young man's embarrassment as she manipulated his limbs and used a field medic's hold to catch and lower him into the chair. He sat massaging circulation back into his hands and feet while she reattached the leads on his scalp that had come loose.

"All right," he said with feigned nonchalance. "Let's get this over with. I don't mind forgetting the rest of today, but I'm having second thoughts about forgetting you."

"For a little while." She touched his shoulder and moved to the podium, striving to order her tattered thoughts. _Focus. Reach for one thing in your mind._ The Doctor's patient tones came back to her, meditation lessons he had taught her as a girl to fortify her against psychic attacks. _Find a focus._ Of course! With swelling hope, she drew out the necklace hidden under her collar and set the crystal atop Lasarti's machine. _For luck_, Tegan might have said.

"What's that?"

"Manussan sapphire." She picked up the dangling mesh of the secondary electrode net, realising with a shudder that she must have been sharing it with the Master. "It stills the mind. It may help me concentrate. Are you ready?"

"Just... one thing." He suddenly looked very shy. "May I have a kiss to... unremember you by?"

She laughed and shook her head. "Incorrigible. No, Lasarti, you'll have to wait. Let our first time remain the first time."

"Damn." He pouted. "Well, I hope I was a good kisser, at least."

"Terrible," she said, eyes twinkling. "And so was I. More study was required. The project involved a protracted experimental phase, with much trial and error." Watching him for signs of discomfort, she activated the sleep inducer.

"Lovely." He leaned back, voice turning drowsy. "The scientific method as foreplay. One of us should write a paper about it."

"I would mention that I adore you, but it might be unhealthy for your ego." She watched his eyes drift shut. "Goodnight, Lasarti."

"See you... Nyssa..." He clung to the name with a beatific smile. "See you in my dreams."

* * *

Tegan closed the office door softly behind her, although she wanted to slam it off its hinges, had wanted to shatter everything breakable in the room before she left. But there was no time. She had to find the Doctor and Turlough. There had to be a way to track another TARDIS, especially the Master's. There must be.

The door vibrated under her fingertips. She heard, or imagined she heard, the ghostly wheeze of a TARDIS returning. Her eyes welled up in despair and rebellion. "I'm not cracking up. I'm not." In the time it took to speak, she realised the sound was more than wishful thinking. Was the Master coming back? _Left the kettle on,_ she thought hysterically.

She was going to make him wishshe had killed him.

With that thought uppermost in her mind, she threw the door open with enough force to dent the wall and charged back inside with no plan at all. Seizing the desk chair and hefting it over her head, she moved to stand belligerently before the bizarre shape of a Greek column materialising where the bookcase had been.

The wait was maddening. Her arms began to shake. "Come on," she growled, judging the best angle to bring the chair crashing down. If she could stun the Master, nip past him, get inside and shut the doors in time— hell's teeth, if she could only make sure he took her prisoner too, so that Nyssa wouldn't have to face him alone—

"Tegan?" Nyssa's voice had never sounded sweeter. "Tegan, it's me. You taught me to dance the Charleston. Put that down and stand back, please."

Tegan dropped the chair with a crash, flinging her arms around Nyssa the instant she emerged. "Nyssa! You wouldn't believe how glad I am to see you. I thought he'd taken you away."

"He had." Nyssa leaned into her, fingertips digging into her shoulders in a way that made Tegan hold her tighter. "But his TARDIS has a fast return switch. Help me carry Lasarti?"

"Lasarti? You've got him! Where is he?"

"In there." Nyssa's fingers sank into what looked like fluted stone. "I've barricaded the Master outside his console room, but I don't know how long the door will hold."

"Right." She pushed through at once, never mind that the Master might be waiting on the other side. He was not, but she nearly tripped over the young man lying on the floor. Chagrinned, she halted to let her eyes adjust to the gloom. An all-too-familiar sight reared out of the darkness, a cruel web spanning one corner of the room from floor to ceiling. "Adric," she choked, remembering its last victim.

"Lasarti," Nyssa said, subdued. Stepping between his feet, she bent and lifted his knees in a practised gesture. "Let's get out of here."

"Oh, Nyssa, I'm so sorry."

Tegan followed her lead, hitching up his shoulders. Guilt and questions needled her as she shuffled backwards. What had happened to him, to both of them? She could see Nyssa retreating behind that wall of reserve that sustained her in moments of crisis, but it couldn't entirely mask her exhaustion, nor the dishevelled signs of a struggle. Just how much time had passed aboard the Master's accursed ship before Nyssa brought it back? How had she escaped his clutches? What if this was another trap, like the Master releasing a doppelgänger of Adric to trick them and send the TARDIS on a one-way trip to destruction? But no. Tegan couldn't, _wouldn't _doubt Nyssa.

Shying away from that dreadful thought, she settled on, "Did you find Lasarti's machine?"

"Yes." Nyssa nodded towards the web. "Hooked into that."

"Ugh! Can't we take it with us?"

"No, but I've wrecked it." Nyssa kept quiet until they had reached the office and were laying the boy on the carpet. "By the time the Master reconstructs it, Lasarti will have perfected it, so I'll have the means to come to the Doctor's aid." She knelt to check Lasarti's pulse and examine his pupils.

"Poor Lasarti. How bad is he?" Tegan said, keeping uneasy watch. She almost wished the Master would show his face so she could hit it with the chair.

Nyssa looked up, eyes softening. "Don't worry. He'll be fine. A little disorientated, perhaps. I put him to sleep to disconnect him."

"Oh!" Tegan relaxed. "Well, that's all right, then. But isn't it going to be conspicuous lugging your sweetheart across campus? Not to mention heavy. No zero cabinet, no wheelchair—"

"We won't have to. I've set a trigger." Nyssa caressed his cheek, gazing at his sleep-loosened features for a long moment as if storing them away. Then she rose and stepped back into the illusory column.

"Hey!" Tegan said. "Don't go back in there!"

"I'll follow you," Nyssa promised. Startling Tegan with a glimpse of that other life she usually kept hidden, she began to sing. "_If I can't be the Jack of your heart, then I guess I'll be a Joker..."_

There was a groan at Tegan's feet. "..._because I like... your... smile..." _Lasarti's eyes fluttered open. "Whoa."

"Welcome back," said Tegan, tearing her eyes away from Nyssa's hiding place. "Heck of a place to work off a hangover."

"Hangover?" His groggy smile dissolved into sheepish mortification. "Well, I hope you enjoyed the party, anyway. Sorry I fagged out on you. You must think I'm a complete prat."

Tegan laughed. "Nice try, Romeo, but you don't have to pretend to remember. I'm not your date." She offered a hand. "Come on. Let's get you out of here before Professor Daskalos turns up."

"Who?" Clambering to his feet, he looked around, perplexed. "This is Dr Crane's office. Wait, no, he's on sabbatical, isn't he?"

She shook her head. "Overwork, that's all. Up and at 'em! That fluffball of yours must be getting hungry."

"Effie! Right you are. Oh, bugger, Daskalos, how could I have forgotten? He's been trying to draft me for an experiment. Did you hear what he did to his seminar yesterday? I'd stay well away from that nutter."

"You can say that again," Tegan said, herding him casually towards the door. "By the way, remember that job offer I told you about? I nicked a pamphlet for you. Oops, that's the back. Ignore the photo. Anyone could look like a bad clone of themselves after one too many all-nighters in the lab..."

* * *

"Well?"

"There you are!" Tegan relaxed as Nyssa slipped out from a kiosk and fell into step beside her. "You're getting pretty good at this spy stuff. Lasarti's all tucked in with that fluffball sitting on his head. Wish I could've brought you a picture. Are you sure he's all right? He was cracking jokes when I left, but he barely remembered me."

"I purged his short-term memory," Nyssa said. "Lasarti agreed it was for the best. I wish I could've stayed to monitor him, but under the circumstances..."

"You did that to him?" Tegan stared at her in disbelief. "Rummaging around in his mind just like the Master!"

Nyssa stared right back with a steely expression. Then she wilted, acknowledging the rebuke. "Yes. Let's go." For a moment, she looked rather closer to her human years.

Tegan flinched, already regretting her words. The sun had finally burned through the clouds, and daylight showed just how pale Nyssa was, apart from the circles under her eyes. Remote and withdrawn, she kept walking faster as if driven by some new, urgent mission.

"Hey! Where are we running off to now?"

"To find the Doctor," she said. "We need to erect a defensive barrier."

"Say what?" Tegan frowned. It was not like Nyssa to be so brusque with her.

"Something the Master said." She started to pull ahead. "We have to prevent him from returning to Zarat."

"How?" Tegan jogged to catch up with her. "So you're going to tell the Doc what happened, after all? What can he do, anyway? Install a bug zapper to fry incoming time machines?"

"Exactly. This way."


	12. Out of Time

"Nyssa, will you just _talk_ to me? I was worried sick about you!" Tegan broke off. Between them and the grove where they had left the TARDIS, the quad was thronged with people. Many were clutching instruments, test tubes, handheld devices, or even potted plants. A hubbub of agitated conversation rose above the milling crowd. Circling security carts were attempting to keep them corralled. "Will you look at that? A nerd herd," said Tegan. "Another fire drill, maybe? Never a boring day around here, is there?"

"Evacuation of the Biohazardous Research Centre, I think," Nyssa said, leading Tegan behind another building to come at the TARDIS more discreetly. "The Doctor's doing?"

"Yeah. If he's there, you can count on it." Tegan snorted. "Maybe we should be running the other way instead." Occupied with keeping wet branches from slapping her face, she kept quiet until they popped out into an open area in the trees. "Hey! Didn't we park the TARDIS somewhere around here? I hope it didn't get towed."

"We did, and it wasn't." Nyssa barely broke stride, jogging past the soggy remains of the art students' decorations. "The Doctor must have taken it."

"Taken it? Where? Nyssa, will you please slow down? _Rabbits_, there she goes again."

Tegan laboured to catch up, heels sinking in the wet earth. Her suspicions were beginning to prickle. Lasarti might be safe, but Nyssa was holding something back. Tegan wished she could stop thinking about the false copy of Adric sent to sabotage the TARDIS while the real boy was being tortured in the Master's web. But she had seen that same web when she helped carry Lasarti to safety. It had been unoccupied, and Nyssa had been with her the whole time.

Except when Nyssa had stepped back into the Master's TARDIS.

"Leave the paranoia to Turlough," Tegan muttered to herself.

Speak of the devil. Beyond the edge of the trees, Nyssa was angling towards a bedraggled, spindly figure hunched on a bench._ Wet rat,_ Tegan thought, still sore at Turlough for abandoning Nyssa to be eaten by moss on their last stopover. Spotting them, Turlough unfolded and leaped to his feet. Tegan could not make out his greeting, but his caustic tones were sharp enough to carry over the irritating drone of an alarm blaring in the distance.

"But that's what I'm telling you!" Turlough blurted as Tegan drew within earshot. "The entire complex is sealed off! There's bulkhead doors all the way down the lift shafts. We're stranded up here, and the TARDIS is eight floors down in an underground bunker. There's no way to reach him."

"Turlough, stay calm," Nyssa said, turning away with an abstracted expression. "Let me think."

He gave Tegan a long-suffering look. "Nice of you two to show up, finally. I don't suppose either of you knows of a dark hole we can crawl into with enough shielding to protect us against a temporal explosion?"

"You're the expert on dark holes to crawl into, Turlough," Tegan shot back. "Actually, I can think of one place, but it's not exactly safe," she said, looking at Nyssa. They had seen more than one TARDIS today, after all. "You don't suppose—"

"No," was the curt reply. "Give me a moment. I'm trying to remember something."

Turlough folded his arms and rolled his eyes. "By all means, take your time. I've always wondered what organ failure feels like."

"Will somebody please explain what's going on?" Tegan said, temper rising. "The Doctor clammed up last night and wouldn't tell us a thing. Nyssa's got banged up somehow and is pretending she's fine. With everything else that's happened, I almost forgot: I felt something really weird earlier, like that time warp we passed through when we crash landed. Is that what this is all about?"

"Well, I have no idea what adventures you two have been up to, but here's what I know. The Doctor is down there." He jabbed a thumb. "So is the TARDIS. And so is somebody's pet science project. Every time it hiccups, it distorts space-time around it. Fast forward a few seconds, a few minutes, a few days, a few decades... If the Doctor hasn't simply cut his losses and run, then he's trying to repair the device before it ages everyone on this planet into extinction. He might have left us the TARDIS to shelter in."

"Got it," Nyssa said, snapping out of her reverie. "I just hope they're using the same codes. This way."

Her friends exchanged dubious glances and followed. She did not go far, but she marched them straight across the paved courtyard where the irritating alarm was loudest. On the far side, Nyssa pivoted and studied at the compass pattern of flagstones as if taking her bearings. Counting under her breath, she began to pace off an arc. She halted next to one of the circular paving stones staggered around the roof's perimeter. Kneeling, she splayed her fingers over the surface, searching.

"A way in?" Tegan said. _Or a trap,_ she thought, trying to catch Turlough's eye. Until now, the rescue mission to save Lasarti had driven last night's discussion right out of her head. What if the Master had something to do with these faulty time experiments?

Nyssa pressed down on two grey divots in the stone. There was a faint pop. At first, Tegan thought nothing had happened. Then she saw that the lip of the roundel now extruded an inch or two above the surface of the flagstone surrounding it.

"Don't be daft," Turlough said. "If this is an emergency ladder, it'll be sealed off with bulkheads like the rest of the complex. Otherwise it's not much of a quarantine."

"Hazmat team access," Nyssa said. "Help— _umph—_ help me lift it, please. The shaft is fashioned like a spiral stair. As the rescue capsule descends, bulkheads pivot into place above it and away just below it."

"So basically it's a giant toilet snake," said Tegan.

They bent to help her pry the hatch open. It flipped over with a clang, revealing the maw of a pipe that was a tight fit for Turlough's shoulders. Handholds and footholds were cut into the walls. It was too dark to see how far the pipe extended or what lay at the bottom.

"Oh, well," Tegan said. "Our day's not complete without at least one tunnel crawl, right?"

Nyssa swung her legs over the side. "There should be room for the three of us."

"With all due respect," Turlough said, "I've spent quite enough time cozying up to Tegan in ventilation shafts. Death by temporal burst may be quicker, or at least quieter. I'll wait up here."

"It'll be even quieter when you stop whingeing," Tegan said. "Come on, Turlough. If that time whatsit explodes, the TARDIS may be our only chance." Without waiting for an answer, she clambered down after Nyssa.

He groaned but gave in, following her down and grousing about the tight squeeze. After a short descent, they found themselves wedged into a cylindrical compartment just wide enough to accommodate three people on friendly terms. Nyssa was tapping a long string of numbers into an old-fashioned pushbutton keypad. She slammed her fist against the wall, depressed a large button to reset, and began again.

"Nyssa?" Tegan tried. "You said you needed to set up some kind of barrier, because of something the M... that Daskalos said." She was mindful of Turlough's pricked ears. "Exactly what did he tell you?"

"Later, Tegan," Nyssa said, voice echoing strangely in the narrow metal chamber.

"You know, you sound just like the Doctor," Tegan growled.

She was not listening, or at least, she was not paying attention. "Thank you."

"That was not a compliment!"

"Curious as I am about your mysterious goings-on," Turlough said, "I think we had better not disturb her. I don't fancy being trapped down here until doomsday. Most security systems only let you get away with a few failed passwords before they lock you out. Or in," he added, looking up at the patch of sky high overhead.

Tegan subsided and stewed. At least the whine of the siren was quieter down here, although something was wrong with it along with everything else. Now and then it seemed to waver, rising or falling in pitch for a split second before returning to a monotone.

"Did you hear that?" Tegan said. The cramped space was making her feel lightheaded. Her stomach gave an unpleasant flip-flop.

"Did you _feel_ that?" Turlough whispered back. "That must be what was bothering the Doctor. The temporal leaks are growing worse."

"Well, my hair's gonna turn white if we're down here much longer."

"That's done it," Nyssa said. Above their heads, the circle of daylight winked out. With a slam of metal on stone, the compartment began to descend in a slow spiral. Every five seconds or so, there was a muffled thud above or below their feet, the concussion of a bulkhead door rotating into position. The compartment was pitch black. Presumably, ordinary rescue crews came equipped with torches.

"Now I know what a drill bit crossed with a jackhammer feels like," Tegan said. "Ugh! I just hope you know how to open the door at the bottom."

"Let's not talk about that," said Turlough. Even in the dark, he sounded green.

"It's automatic," Nyssa said. "The trouble is, I can't be certain this is the right access point. This whole quadrant of the building was ripped out and rebuilt before I started work here."

"Funny that," said Turlough.

"Great," Tegan said. "This car can go back up, right?"

"Yes." It was slowing. "However, exiting a contaminated area requires a higher level of authorisation, and I may not be able to hack the codes. Here we are."

The car juddered to a halt. There was a suspenseful pause. Finally, the compartment rotated one more half-turn, opening onto an empty hallway. They tumbled backwards like air cushions popping out of a tightly packed shipping box. Tegan and Turlough stood squinting and shielding their eyes, waiting for their vision to adjust to the sterile full spectrum lighting.

They found themselves in a dead end blocked by discarded equipment draped under plastic sheeting. An emotionless PA announcement had replaced the droning alarm, but it was not much of an improvement. "QR Quarantine Phase Three. Please move to a secure area and wait for emergency teams to reach you. QR Quarantine Phase Three. Lifts and stairs have been sealed for your protection."

Another wave of vertigo hit them. It lasted for less than a second, just enough time for Turlough to yelp and clap his hands over his ears. After it was over, Tegan ran her fingers through her hair and raised her eyebrows at him in a silent question. She was only half joking.

"I knew it!" he moaned, misunderstanding. "Don't tell me. How old do I look? Is my hair white? I've lost it, haven't I?" He patted the top of his head.

"You certainly have," Tegan said, breaking into a chuckle. "But your hair's fine."

"Very funny." He glared at her. "I should tell you that yours is looking very distinguished. But of course that's a lie." The jibe sounded forced. His pale eyes were so wide that the whites stood out starkly.

Realising he was well and truly spooked— who knew how long he had spent on that bench fretting— she swallowed her next retort. "Nyssa?"

While they were trading barbs, Nyssa had pushed past the barricade of lab equipment to a nearby wall where a directory panel was flashing the same warning as the PA system in large block letters. "Show me the way to the cryogen lab," she said.

The screen cycled through a series of different colours and languages, but gave no other response.

"Medical emergency clearance zed stroke ten alpha niner," she said. "Show me the way to the cryogen lab." A map lit up with an illuminated path. "Good. Not far. This way."

Tegan groaned as she took off again. "I've spent all morning running after her."

"Story of our lives," Turlough said. "Come on. At least we're not going to die in a torpedo tube."

* * *

Nyssa had guessed correctly. Bulkheads sealed off the corridors in almost every direction, but just around the corner was a hallway almost identical to that outside her own laboratory. Turlough gestured to the pressurised doors halfway down. "That's the cryogen lab," he said, hanging back. "Sealed, of course."

The door's hand sensor refused to respond, but another medical override established their credentials. It took the combined strength of all three of them to drag the heavy doors open manually. As soon as there was a sufficient gap, Nyssa squeezed through, plunging into dead, stale air laced with trace odours of long-decayed organic material. At least there was enough oxygen left to breathe. Or was there? The slight _whoosh _of air rushing in from the corridor worried her.

"Nyssa, wait!" Turlough said. "It's too dangerous."

"Something's gotten into her," Tegan fretted.

The laboratory's lighting had failed, but a familiar blue-white glow illuminated the far end of the room. Nyssa started towards it, surveying the complicated scaffolding that surrounded what she assumed to be the source of the temporal disturbances. Whatever it was, the comforting silhouette of the police box stood directly between them and it. At least the TARDIS' shielding might provide some slight line-of-sight protection. Unfortunately, its doors were facing away from them.

"The TARDIS!" Tegan said behind her. "At last."

As she started towards it, a feeble glow to her left caught Nyssa's attention.

"Wait." Turlough caught Tegan's shoulders. "Get too close, and the time distortions could be lethal. You don't want to know what happened to the last person I saw cross the room."

"There's someone over here," Nyssa said, heading to the solitary illuminated cryogen tube in the near corner.

"Not the Doctor!" Tegan said, alarmed.

"Too short. I think it's Professor Xertes," Turlough said, peering past Nyssa at the motionless figure obscured by a white haze inside the tank.

"She's in suspended animation," Nyssa said.

"Tegan?" the Doctor's voice drifted out of the shadows. "Turlough? Nyssa? How on Earth did you get down here?"

"Emergency medical access," Nyssa called back. "Doctor, are you all right?" Disregarding Turlough's warning, she hurried across the room, feeling her way through the maze of equipment and keeping in the lee of the TARDIS as long as possible.

"There's no time. Into the TARDIS, quickly now! Disconnect the console, toss the cables outside and close the doors. I'll join you shortly, after I've taken care of—" His voice turned gravelly and broke off. "Ah. Once I've finished up here."

"What are you up to, Doc?" Tegan said, veering towards the sound of his voice. "Ow!"

"Mind the cryogen tanks," Turlough said. He sneezed at the fine powder of rust and decayed insulation kicked up by their footsteps. "Doctor, I don't suppose you can tell us exactly how long we're to wait in the TARDIS while you finish saving the world?"

Nyssa needed no invitation. Dodging around the police box, she saw the Doctor hard at work on one knee, surrounded by a jumble of cables, tools, and discarded casing strewn across the floor. She was relieved to see he was physically unchanged, apart from pallor and several days' stubble. His face was coloured unnaturally by the ominous bright lines zigzagging ever higher on the tachyon meter propped beside him. He was no longer paying any attention to it, too engrossed in making delicate but urgent adjustments to the exposed filaments inside Xertes' machine.

"Stop!" he said, hearing her footsteps. "Don't… come any closer. Temporal energies in flux. Nyssa, if the HADS activates, take the TARDIS forward in time until it's safe. I'll find you there."

"HADS?" Tegan said, taking in the tableau as she joined Nyssa. Sidling around the corner, Turlough gave both of them an exasperated look and scurried into the TARDIS.

"Hostile Action Displacement System," Nyssa said, distracted. "Doctor, wait. You can't keep this up for much longer. What happens if this device goes critical?"

His silence was answer enough. The Doctor was doing everything he could to maintain a dangerously unstable containment field. That much was clear from the tachyon readings. His rigid back and shoulders were more eloquent than an alarm. A horrible feeling of déjà vu made Nyssa take a step closer to Tegan. In her mind's eye, she could see that black pall stealing across the TARDIS scanner to devour the worlds of the Traken system one by one, her own planet the last to go. Now her second home teetered on the brink of entropy as well. "Doctor, there's five billion people on this planet," she said. "We can't save ourselves and leave them to die."

"Do we get a vote on this?" Turlough shouted. A heavy cable came flying out through the doors, bounced off Tegan's calf and dropped to the floor.

"Ow! Turlough, watch where you're throwing that!" Tegan said, hopping on one foot. "Can't we just bin the thing? I dunno, take it away somewhere so it can't hurt anybody?"

"Move it how?" Turlough called. "That's dwarfstar alloy. It must weigh as much as a city. Come on, you two, give me a hand in here."

"Well, then, what if—" and Nyssa's heart leapt at Tegan's magic word _if_, which she had once called the most powerful word in the English language— "what if the Doctor materialises the TARDIS around it, then chucks it into the time vortex? That's where we crashed into that shockwave, right? Maybe that was this thing blowing up!"

"Tegan, that's brilliant!" Nyssa said. "Doctor, if we jettison the room where—"

A buzzing alarm from the tachyon meter threw the Doctor into a frenzy of motion. For several tense seconds, he was weaving around Xertes' machine, adjusting dials and fiddling with connections. Nyssa seized Tegan and backpedalled into the entryway of the TARDIS. They watched helplessly while Turlough bellowed at them to move so he could close the doors. For a terrifying moment, Nyssa thought the Doctor had lost control. Then he dropped to his knees before the open panel where he had been working when they entered, and resumed his single-minded activity.

"Doctor?" Nyssa pleaded.

"Very well," he said, hoarsely enough to tell her just how close they had come to annihilation. "Tegan. Inside, now, no more arguing. Help Turlough. Nyssa, can you manage it? Precision short hop to surround the device in a secondary room, dematerialise, immediate jettison. Make absolutely certain you enclose Xertes' device in the same room you delete. And then—"

"Lateral jump to escape the blast zone before the field ruptures. I understand." She mirrored his self-assured tone, shoving back panic. This was a far more complicated manoeuvre than anything she had ever attempted under his supervision. He was gambling. He was throwing dice into a singularity and waiting for double sixes to pop out, and Zarat was doomed unless she could somehow live up to his lunatic hope. Despite the danger, she edged towards him. "The TARDIS will help. She's fond of me, you know."

"I know," he said, the sound of a smile breaking through the strain as he lowered his voice. "Take care of her, will you? Don't let the Time Lords melt her down for scrap."

"Doctor!"

"It's all right," he whispered. "_Go._ If I'm to die saving a planet, I can't think of a better one than yours."

An apology for Traken. She knew exactly what he was doing, and there was no time to debate false equivalences or even to say goodbye. Wrenching herself away, she fled to the safety of the TARDIS.

Moving to the console without a word, she forced herself to focus on the task at hand, programming a complex series of steps for the ship to follow in near-instantaneous succession. Timing... they were out of time, and yet she had to allow for time itself to vary, not to mention dwarfstar's extraordinary mass... Her head was throbbing again, and she had to check every command line twice. She knew she was not functioning at full mental capacity.

If only Adric were still alive.

"So what's the plan?" Turlough said, hovering by the inner door as if debating whether to bolt for the deepest part of the TARDIS he could find.

"Nyssa?" Tegan said, unscrewing the last cable and heaving it outside. "What did the Doctor say? What did he ask you to do?"

"Please don't distract me," she said. "If I get this wrong, we'll lose either the TARDIS or Zarat."

"Or the Doctor," Turlough said.

"No offence, but I hope he checks your sums before we take off," Tegan said.

Nyssa did not answer. She paused only once to take the ion bonder out of her pocket, give the bottom a twist, and set it down next to the door controls.

"She's plotting something," Turlough remarked matter-of-factly. "Nyssa, just spit it out. The Doctor's trying to sacrifice himself again, isn't he?"

Her eyes were wet. It was not true that she never wept, but she needed to concentrate. She could not afford blurred vision right now.

"Nyssa," Tegan said, low and sharp. "The Doctor won't have time to get clear, will he?"

"I know."

"What about that future you saw? Didn't we just go through all that rigmarole to make sure the Doctor still has one?"

"I _know_." Nyssa raised her voice, a stranger speaking through it. "Doctor, we're ready."

"Good luck!" the Doctor sang out. "See you shortly!"

"Turlough," Nyssa said. "Close the doors."


	13. Deferred Choices

"Right," Turlough said. "Let's get out of here."

"Don't you dare!" Tegan threw herself at Nyssa, grappling her and hugging the arm that was reaching for the dematerialisation switch. "Turlough, don't _you_ dare! Keep your filthy hands off those controls!"

"Tegan, there's no time," Nyssa said, struggling. "When that field ruptures, we'll be killed along with everyone on this planet!"

"Turlough, she's not herself," Tegan said, trying to drag her away from the console. "And I don't care what the Doctor said. We're not leaving him!"

Turlough's hand dropped, but it fell on the ion bonder instead of the door lever. Giving Nyssa a murderous look, he rushed outside.

The Doctor barely had time to glance up at the sounds of commotion before a green beam of light struck him from behind. He fell forward with a thump onto Xertes' machine. Steeling himself, Turlough darted forward, seized the Doctor's ankles and began dragging him back towards the TARDIS. The flashing meter on the floor shifted to an urgent three-tone alarm.

"Hurry, Turlough!" Nyssa called. "Tachyon readings at critical!"

"So come out here and help!" he barked. However, before Tegan could make up her mind whether to release Nyssa and lend a hand, Turlough's self-preservation instincts kicked in. He lifted the Time Lord bodily, reeled across the lab and pitched headfirst over the TARDIS threshold, kicking the Doctor's legs clear of the doors. Tegan punched the door lever with her elbow. There was an ominous popping, cracking sound of strained metal beginning to give way as the doors swung shut. It sounded as if the near half of the laboratory was crashing down around them.

Shrugging free of Tegan's grasp, Nyssa quietly reached past her to press the dematerialisation switch, forgoing the Doctor's dramatics. The time rotor began to rise and fall. The resonant _choom_ of the initial downstroke sounded perfectly normal. Then came that awful juddering noise they had come to dread. The TARDIS began to shake. The grinding din escalated rapidly, rising to a wail like the dying yowls of some vast primordial creature being dragged down the gullet of a black hole. There was a sickening sideways yaw. They felt curiously suspended, disembodied, as if space itself was ebbing away.

"What's happening?" Tegan gasped, clinging to Nyssa.

"Temporal surge..." Her voice rose to an impossibly high pitch. The rotor rose and plunged at a speed that defied human sight. Turlough's yell was lost in a screaming, shearing roar as the floor sliced sideways and threw them off their feet. Then it was over. The central console slowed to a steady, regular pulse, the gentle TARDIS hum reasserted itself, and the floor stopped trying to part ways with the rest of the room. A haze of white smoke began to pour out of the console.

"Here we go again," Turlough grumbled, rolling over to check on the Doctor. He was asleep, pale as his jumper, blissfully unaware of his ship's travails. Nyssa, who had fetched up in a heap under the console, raised her head to check on her friends, then let her chin drop onto her arms as if she planned to take a nap.

"I'm not helping you up," Tegan said, standing over her with hands on hips. "You were going to scoop up the Doctor right along with that horrible machine and toss him out to die in the time vortex! Nyssa, how could you?"

"No, she wasn't." Dusting himself off, Turlough gave Nyssa a sour look and set the ion bonder back on the console. "Saint Nyssa the Immaculate's reputation remains spotless. No one would ever suspect her of being more devious than I am." He reached under the console and righted the small woman rather more gently than his sarcasm would suggest. "Congratulations."

"Thanks," Nyssa said faintly as he hoisted her to her feet. She leaned into him. "That was very brave, Turlough."

Clearing his throat, he patted her back awkwardly. "Maybe I was more scared of Tegan."

"Oh, Nyssa!" Tegan's eyes widened. "You set us up."

"I'm sorry, Tegan. The Doctor warned us not to get too close to that machine. What if it had killed you? I couldn't ask that. It had to be your choice." She held out a hand and drew Tegan in as well, hugging her fiercely. "Thank you both. Please don't tell him."

Turlough snorted. "My lips are sealed."

* * *

"The Doctor says he'll trade you a medical kit for the orange juice. He also ordered you not to go anywhere near the controls again, until that head of yours—" Tegan pulled up short just inside the door. "Hey! What happened to your room?"

Nyssa's lab bench and all its equipment had disappeared. In their place were the whimsical furnishings of a girl's room: scalloped dressing table and mirror, plants in tall vases, a fluffy white carpet, art nouveau lamps, one of the peacock chairs, and a twin bed that had somehow migrated back from Tegan's room. Nyssa was lounging under an old-fashioned lace bedspread in her pyjamas, propped up on pillows with an icegel compress behind her head. Yawning, she pushed away the book slipping off her knees and sat up. "Scattered across the vortex, I expect. I wish there'd been time to embed a telemetry probe. The disintegration would have made a fascinating study."

"You jettisoned all your stuff?" Tegan looked around in growing dismay. "Ann Talbot's butterfly costume? Oh, Nyssa, your china collection. And... oh, no, the Richter's cure!"

"It's safe. I deposited it in the main lab of the TARDIS yesterday. Thank you for reminding me. I ought to run a few tests."

"Not today," Tegan insisted, coming over to perch on the edge of the bed. A flutter of burgundy and violet tulle distracted her. Looking up, she was dumbfounded to see the pretty but impractical Trakenite court garb that Nyssa had been wearing on the day they met. "What happened here? Something to do with temporal distortion?"

"My room was expendable, and I knew its precise coordinates," Nyssa said. "Unfortunately, the TARDIS' internal architecture database is corrupted. All it could find was the oldest saved file for my quarters. It doesn't really matter."

"I guess not." Tegan's face fell. It was a blunt reminder that Nyssa did not intend to stay. "But you can't leave quite yet. The Doctor says he wants to stop off somewhere called Vektris for repairs. I don't think he likes your driving. If you ask me, the TARDIS has been acting up ever since Turlough slithered on board. Can a time machine have an allergic reaction to somebody?"

"Tegan," Nyssa scolded.

"Oh, good, you're back to normal." Tegan chuckled at Nyssa's exasperated huff. "Now stop hiding under there and let's get you patched up. You're not fooling me." She unsnapped the top of the kit and wiggled a tube in front of her nose. "Remember this stuff?"

"I'm fine, really. Just a headache." Nevertheless, she submitted without further protest. The salve could heal bruises, but not the deeper abrasions left by the Master's mental trespass. Still, a friend's touch helped there, too. Only when Tegan insisted on unfastening her collar did she balk. "Don't look so worried," Nyssa said, reading her distraught expression. "I had to let him get close enough to stun him. He didn't realise I was armed."

Tegan tried to smile as she dabbed at the faint marks around Nyssa's neck. "Sounds like you gave as good as you got. Wish I'd been there to help."

"So do I. I missed you." She closed her eyes and settled back, relaxing as the analgesic began to sink in. "You took Lasarti away just in time, by the way."

"Huh?" Tegan paused her ministrations with a puzzled frown. "Oh, for heaven's sakes. I can't leave you alone for five seconds, can I? Don't tell me you got into another scrap with the Master after we left!"

"Not really," Nyssa said. "He just needed to salvage his wounded pride by gloating..."

_Nyssa trailed after Tegan and Lasarti as the office door closed behind them with a click of finality. She drew the bolt to make sure. "See you soon, Lasarti," she whispered, feeling a tug like an invisible thread playing out from the spool of her heart as their voices faded away. She longed to follow, but time's fences were closing around her once more._

_Waiting for Tegan to get clear, she heard a soft scuff on the carpet behind her. She folded her arms and turned, blocking the exit. "Oh. It's you."_

_"Tsk. Manners, my dear, manners." Garbed once more in ostentatious black velvet, the Master lounged against the faux stone column, gloved hand cradling the slim black weapon aimed at her head. "But where is the Doctor? His last-minute rescue is surely overdue."_

_She shrugged. "Not coming, I'm afraid."_

_"Not coming? Oh, that does not sound like him at all. Even at his most thickheaded, he should have noticed your absence by now. Could you possibly be lying, my dear?"_

_"I told him to leave. This is my home, after all. He'll be going as soon as Tegan gets back."_

_"And he... _obeyed_ you?" He laughed, lingering over his favourite word. "Well, well, you've outgrown him, I see. Excellent. Perhaps I haven't lost you after all. Come, Nyssa. What could be more perfect than father and daughter traversing time and space together, sampling the wonders of the cosmos? And there is still so much I could teach you. Nyssa, my dear, come back to me."_

_Even now, his hypnotic cadences were oddly soothing. The delicate suturing of Lasarti's memories had left her mentally fatigued, depleting her psychic defences. Her body ached with more bruises than she could remember since her cruel imprisonment on Veln. Her heart still inclined towards her father's musical voice like flower to sun, even if reason rebelled. She could feel her muscles going slack. Stamping her heel to shake herself awake, she turned her back on him and reached for the door._

_She heard the Master's hissed intake of breath. At least she had surprised him. The skin between her shoulder blades prickled, as if flesh could sense the deadly weapon trained upon her back._

_He spoke with grudging respect. "No? A pity. Perhaps I'll return in a few years and check on my son-in-law's progress. Until we meet again, Nyssa."_

"...and then he left," Nyssa concluded baldly. "That's what I was fretting over when I found you. I'm afraid I was rather short with you. I apologise."

"It's all right. You'd had a time of it. I was just afraid that—" Tegan's voice hitched. "Hey, I'm the one who should be apologising. I nearly got you and that boy killed!"

"No, Tegan, you didn't." It was her chiding tone again, but fond. "Or, if you put it that way, I nearly got _you_ killed. Remember what the Doctor used to say about being in the wrong place at the right time? If you hadn't helped me find a way aboard the Master's TARDIS, Lasarti would still have been kidnapped, but they could be anywhere in time or space by now. We'd never have been able to find him."

"Yeah, maybe." Tegan sighed. "I just wish I'd been able to keep him safe, like you asked."

"Ultimately, you did. You were the one who figured out how to channel that tachyon explosion into the vortex."

"I don't see what that has to do with— oh! That's your bug zapper!" Tegan slapped her knee. "The Master won't be able to penetrate that tachyon field, will he?"

"The temporal distortion should settle in time, but I think he'll lose interest in Lasarti once he's rebuilt his own version of the device. So my family is safe." Her eyes softened. "Besides, I have you to thank for sending Lasarti to Terminus in the first place. So, you see, I owe you for rather more than keeping him out of the Master's clutches."

"Well, yeah. If you put it that way." Tegan grinned. "When do I get an invite to the wedding?"

"You already did, but it seems to have gone astray somewhere between Terminus and the TARDIS."

"I'll just have to come to your fiftieth, then!" Tegan finished dabbing ointment on the bruises she could see and looked up. "Okay, anything else?"

"Well..." Nyssa pushed her hair off the nape of her neck. "Not pretty, I'm afraid."

"Ow. That's a nasty knock. No wonder you were being a pill." Tegan slathered the swollen lump gingerly, biting her lip when Nyssa flinched. "Sorry. Maybe we should get you to a real doctor when we land. Just to be sure?"

"A real doctor says it's a mild concussion, the patient's pupils respond normally to light stimulus, and three to seven days' rest are indicated. As I recall, Vektris is a resort planet, so that's exactly what's in store for us." Nyssa touched her hand. "Thanks. That feels much better."

"Three to seven days," Tegan said, screwing the lid back on the salve and addressing her fingernails. "Let's... let's make it seven, okay?"

"I expect that will be up to the Doctor. Or, really, the TARDIS." She watched as Tegan made a show of tidying up the medical kit before setting it on the floor. "Tegan."

"Mmm?" Tegan wiped an eye furtively with a knuckle.

"You could come with me, you know," Nyssa hitched around so that they were sitting side by side. "You'd be welcome to stay."

"What?" Tegan's head came up with a jerk. "Stay where? On Zarat?"

Nyssa slipped an arm behind her shoulders. "You're family, Tegan. I've told Lasarti and the children all about you. They'd be delighted to meet you— properly, this time."

"Oh. Um, thanks," Tegan said, bemused. "Wouldn't it be a little weird, with me looking like one of your kids? And Lasarti's pushing sixty now, right?"

"Yes, but synthetic DNA augmentation and other medical advances have extended human longevity."

"There you go again with your science mumbo jumbo. I bet your whole family talks like that. Hang it all, without the TARDIS' telepathic circuits, I wouldn't be able to understand a word you're saying, would I?"

Nyssa smiled. "I've been speaking English with you ever since Amsterdam. The Doctor taught me while you were away. But yes, you'd have to make do with conventional computer translation, until you learned Zarachi."

Tegan looked torn. "I'm not ready to say goodbye to you, Nyssa. Really, I'm not. But..." She shook her head. "I'm not ready to say goodbye to Earth, either."

"I understand," Nyssa said. "I'm facing the same dilemma. It's selfish of me to put the onus on you. Just… please know that you'll always have a place wherever I am."

Tegan released a quavery breath. "Thanks."

"Well." Nyssa gave her a playful shake. "Enough heavy thoughts. Let's make the most of our holiday on Vektris, shall we? We can relax, enjoy the sunshine, sip drinks and do absolutely nothing for a change."

"Sounds great." Tegan turned to hug her back. "Now, get some sleep. That smart doctor-lady said you ought to rest. If I were you, I'd listen to her."

* * *

Some hours later, Tegan stood at the door to the console room, pensive. "Doctor, do you know where Nyssa's got to? She was sleeping earlier, but she's not in her bed. Turlough hasn't seen her either. You don't think—"

"Don't worry." The Doctor looked up from the controls. "I've been here since supper. Nyssa won't give us the slip."

Tegan relaxed. "Not that we want to hold her prisoner, eh? It's just..."

"I know." He flipped a few switches to lock down cruise mode, then stepped away from the console. 'It's been a long day, Tegan, for you as much as for anyone, I suspect. Get some rest. I'll find her."

"Thanks."

Once upon a time, the Doctor would have found Nyssa in the arboretum. Long ago, he had reconstructed a small grove of trees from her homeworld as a coming of age present. It had been worth all the labour of sifting through Gallifreyan databanks to tease out that rare bright smile from a girl who almost never cried, but seldom laughed. Now, however, she was no longer a child to take refuge in her bower when life outside the TARDIS became too much to bear.

The library was empty. He turned his steps towards the laboratory, careful to enter quietly so as not to disturb the slight figure bent over the eyepiece of a sophisticated scanner. Just as he entered, she made a frustrated growl and raised a fist to slam it against the lab bench.

"Easy," he said. "It's less sturdy than the TARDIS console."

"Oh, Doctor," she said. "I'm sorry."

"No need to apologise, I just didn't want your samples to go flying." He nodded to the medical canister sitting next to her with the lid open. "What's wrong?"

"The Richter's cure. I think it's changed, although I'll have to sequence it to be sure." She frowned. "I know how little you enjoy routine maintenance, Doctor, but a third of this equipment needs recalibrating, and another third needs replacing. To say nothing of your fondness for antiques."

"If you don't appreciate antiques, you shouldn't have taken up with a Time Lord," he retorted. "Most of my companions care more about the wardrobe and food machine than the quantum scanner. However, point taken. Perhaps you can provide me with a shopping list before you go."

"If I were staying, I'd tackle some of the maintenance for you." Nyssa sighed, closed the medical canister and ran a thumb around the seal. "How's the TARDIS?"

"Limping. She's never been the same since our crash landing on Terminus, but lately she's been shedding rooms every time we materialise. If I can't isolate the fault, I may have to rebuild her interior from scratch. And then, perhaps, we can take you wherever you need to go."

"Terminus," she said. "I can catch a shuttle from there."

"Of course." He bowed his head. "Don't stay up too late working. As long as you're here, you have time. And... Nyssa?"

"Yes?"

"I'd like my ion bonder back, please."

"Oh, right." She drew it from her dressing gown and held it out, unrepentant. "The Master didn't approve, either."

"Hm." He reclaimed it and shoved it into his own pocket, from which she doubted it would be unearthed for the next half-century. As he stepped close, his eyes travelled over her as if scanning a circuit board for damage.

"Vektris sounds lovely," she said mildly. "Tegan and I are very much looking forward to it."

Brows knitted, he opened his mouth, closed it again and turned to go.

"Doctor?"

He stopped with his fingers on the door handle.

_Let's make it seven, okay?_ Tegan's plaintive words drifted back to her. "I find that I'm... not quite ready to leave. It's selfish, but I'd like a few more good memories of you all to carry with me. Some new stories to tell when I return home."

"For old time's sake." He turned back, leaning against the doorframe. "Good memories, eh? You know, it occurs to me that Tegan's never seen Stockbridge."

"No, Doctor, not this time. I'd like something more interesting than cricket, please," she said, just to see him pout. "Surely there's a fascinating biosphere you always meant to show me, or an unusual solar system, or an ancient ruin. Perhaps even someplace safe, if you can bear three monster-free jumps in a row."

He looked aggrieved. "Where's the fun in that? You were never this picky as a girl."

"Go away." Fan-lines crinkled around her eyes. "Goodnight, Doctor."

"Nyssa." For a moment, the old man peeked out from behind the young man's eyes. "Before it slips my mind. I think you mentioned something about your past, my future. I'm not at all sure I had the chance to thank you properly, when—"

Her heart tightened. "Now, really, Doctor. I oughtn't to answer that."

"Oh, good." The bright, boyish grin returned. "Goodnight, Nyssa."

She stared at the door as it closed silently between them. It was comforting to know that when she left, he would still have one more appointment to keep with her younger self in that place where dreams and death were akin. Eyes glistening— but she never wept openly, not for Traken, not for her father, not for Adric, not for the all-too-human Time Lord who had striven to fill her father's shoes— she turned back to her work with a sad smile.

"You did, Doctor. And you will."


	14. Author's Note

_Thanks so much for reading! If you enjoyed this story, I'd love to hear from you in the comments!_

**Where to find these old Doctor Who characters if you want to know more about them...**

A good fanfic should be stand-alone, so that someone who doesn't know the fandom can jump in and follow and enjoy the story.

However, obviously, this is chock-full of references to some great classic _Who_ episodes over the years.

**_TELEVISION: _**

First of all: **Keeper of Traken • Logopolis • Castrovalva**  
The Master destroys Nyssa's home planet, steals her father's body, kills Tegan's aunt, wipes out a third of the universe, and kills the fourth Doctor— and that's just the first two stories. In the last one, Nyssa and Tegan help the confused, newly-regenerated Doctor heal and escape a bizarre village where the Master has trapped them.

Second: **Arc of Infinity.** Not the greatest episode, but it's got Nyssa acting as the Doctor's loyal defender against the Time Lords. Pacifist though she is, she holds the High Council of Gallifrey at gunpoint to save him.

Third: **Kinda **and **Snakedance.** These are famous classic _Who_ stories, in which the Mara, an evil spirit in the form of a snake, first possesses Tegan and then uses her to infect or terrorize others. If you can find the _Kinda_ remake with some CGI touch-up on the snake, it's powerful; if not, just pay attention to the story and forgive the bad special effects.

_**AUDIO: **_

Fourth: There's a ton of great Five &amp; Nyssa audio episodes that Big Finish shoehorned in after the end of season 19, when the Doctor left Tegan in Heathrow, and the end of _Arc of Infinity,_ when she returns. Recommended: **The Game, Primeval, Fanfare for the Common Men, 1001 Nights, **or (for laughs) **Castle of Fear,** which is one of their few light-hearted stories. The friendship, love, respect and trust between Nyssa and Five comes out in these wonderful episodes in a way that classic _Who_ TV scriptwriters only glimpsed.

Fifth: **Circular Time.** This Big Finish audio is an anthology of stories exploring the evolution of the Doctor and Nyssa's friendship over the years. Part Four is the fifth Doctor's dream/hallucination that takes place entirely in his mind as he's dying. This story introduces Lasarti, his lucid dreaming machine, and Nyssa's use of that machine to reach the Doctor's mind and help him escape the Master's dream-trap.

**And Finally:**

Big Finish Audio's classic Who stories with the actors of Five, Nyssa, Tegan and Turlough reuniting to record all-new adventures, which can be purchased for download or CD on their website. There's 12 stories with this batch of classic Who actors/characters so far, with another trilogy due in 2015. **Cobwebs**, **Cradle of the Snake**, and **Emerald Tiger** are my favorites, or **Heroes of Sontar** for a comic relief episode.


End file.
